feat: deferred 1a items - menu_rev lock, lit_mcp_guides filter, warnings, schedule guard precision

Task 14 (rulings P17/P18, Q10):
- lit/menu-get returns menu_rev (Rev::ofMenu over id, parent, position,
  title, url, object, object_id); lit/menu-set-items requires it, refuses
  a stale one with rev_mismatch (hint: lit/menu-get) and returns the new
  menu_rev. Errors::revMismatch takes an optional message/hint.
- GuideRepository: filter lit_mcp_guides adds/overrides topics; invalid
  topic names and non-string content are ignored, files stay the default.
- lit/post-trash names front page, posts page and linking menus in the
  confirmation and as warnings; lit/menu-assign-location needs confirm
  to remove an assigned menu and names it; lit/post-schedule warns that
  a private entry becomes public; Divi hints no longer point to
  non-existing lit-divi-* tools.
- PostGuard::missedSchedule: 60 s publish window, zero GMT date falls
  back to get_gmt_from_date(post_date); post-schedule refuses dates
  within that window.
- write_failed after a clean rollback that keeps a revision/backup says
  "Die Aenderung wurde nicht gespeichert (... bleibt erhalten)" via the
  new state parameter (Errors::writeFailed / WriteFailed rolledBackState).
- wp-basis-smoke: menu_rev flow, unassign confirm, trash/menu and
  private-schedule warnings.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01At3V6SjwbMe6eMzVGW3Hs7

src/Abilities/Errors.php

@@ -56,13 +56,14 @@ final class Errors
         return self::make('not_found', $message, $hint, 404);
     }
 
-    public static function revMismatch(): WP_Error
+    /** $message/$hint replace the post-oriented defaults (e.g. for the menu lock menu_rev). */
+    public static function revMismatch(?string $message = null, ?string $hint = null): WP_Error
     {
         return self::make(
             'rev_mismatch',
-            'Der Inhalt wurde seit dem letzten Lesen geändert; nichts wurde geschrieben.',
-            'Neu lesen (z. B. lit/content-get, direkt: lit-content-get) und die Änderung auf dem aktuellen Stand '
-                . 'wiederholen.',
+            $message ?? 'Der Inhalt wurde seit dem letzten Lesen geändert; nichts wurde geschrieben.',
+            $hint ?? 'Neu lesen (z. B. lit/content-get, direkt: lit-content-get) und die Änderung auf dem aktuellen '
+                . 'Stand wiederholen.',
             409
         );
     }
@@ -105,12 +106,18 @@ final class Errors
      *
      * @param array<string, mixed> $details Extra error details (e.g. a backup that stays).
      * @param string|null          $hint    Replaces the default hint (e.g. "re-read before retrying").
+     * @param string|null          $state   Replaces "Nichts wurde gespeichert." when the rollback left
+     *                                      something behind on purpose (a backup or revision).
      */
-    public static function writeFailed(string $reason, array $details = [], ?string $hint = null): WP_Error
-    {
+    public static function writeFailed(
+        string $reason,
+        array $details = [],
+        ?string $hint = null,
+        ?string $state = null
+    ): WP_Error {
         return self::make(
             'write_failed',
-            trim('Speichern fehlgeschlagen: ' . $reason) . ' Nichts wurde gespeichert.',
+            trim('Speichern fehlgeschlagen: ' . $reason) . ' ' . ($state ?? 'Nichts wurde gespeichert.'),
             $hint ?? 'Eingaben prüfen, ggf. korrigieren und erneut versuchen; tritt der Fehler wieder auf, den '
                 . 'Administrator informieren (Details im PHP-Error-Log der Website).',
             500,
@@ -118,6 +125,16 @@ final class Errors
         );
     }
 
+    /**
+     * The $state for writeFailed() when a clean rollback deliberately keeps something, e.g.
+     * "Revision 811" or "Sicherung 88": the change itself is not saved, but "Nichts wurde
+     * gespeichert" would be untrue.
+     */
+    public static function notSavedKeeping(string $kept): string
+    {
+        return sprintf('Die Änderung wurde nicht gespeichert (%s bleibt erhalten).', $kept);
+    }
+
     /**
      * A write failed and could not be rolled back completely – something may have been saved.
      * $state and $hint replace the post-oriented defaults for writes that are not about a post

src/Abilities/Rev.php

@@ -33,6 +33,32 @@ final class Rev
         ]));
     }
 
+    /**
+     * Rev of a menu ("menu_rev", optimistic lock of lit/menu-set-items): covers, per item in
+     * menu order, exactly what lit/menu-set-items compares and writes – id, parent, position,
+     * title, url and linked object. Other item data (classes, target, …) is never rewritten
+     * by the tool and therefore not part of the lock.
+     *
+     * @param list<object> $items wp_get_nav_menu_items() result.
+     */
+    public static function ofMenu(array $items): string
+    {
+        $rows = [];
+        foreach ($items as $item) {
+            $rows[] = implode("\0", [
+                (string) (int) ($item->ID ?? 0),
+                (string) (int) ($item->menu_item_parent ?? 0),
+                (string) (int) ($item->menu_order ?? 0),
+                (string) ($item->title ?? ''),
+                (string) ($item->url ?? ''),
+                (string) ($item->object ?? ''),
+                (string) (int) ($item->object_id ?? 0),
+            ]);
+        }
+
+        return self::of('menu' . "\1" . implode("\1", $rows));
+    }
+
     /**
      * Whether $input carries the current rev of $post (optimistic lock of the post tools).
      *

src/Abilities/WriteFailed.php

@@ -15,7 +15,8 @@ use WP_Error;
  * lit_write_failed when everything was rolled back, lit_partial_write otherwise.
  * $state/$hint customise the partial-write error for writes that are not about a post (see
  * Errors::partialWrite()); $details are added to either error. $rolledBackHint replaces the
- * default hint of the write_failed error.
+ * default hint of the write_failed error, $rolledBackState its "Nichts wurde gespeichert."
+ * (for rollbacks that deliberately keep a backup or revision).
  */
 final class WriteFailed extends RuntimeException
 {
@@ -30,7 +31,8 @@ final class WriteFailed extends RuntimeException
         public readonly ?string $state = null,
         public readonly ?string $hint = null,
         public readonly array $details = [],
-        public readonly ?string $rolledBackHint = null
+        public readonly ?string $rolledBackHint = null,
+        public readonly ?string $rolledBackState = null
     ) {
         $internal = $detail !== '' ? $detail : ($previous !== null ? $previous->getMessage() : $reason);
         parent::__construct(
@@ -43,7 +45,7 @@ final class WriteFailed extends RuntimeException
     public function toError(): WP_Error
     {
         return $this->rolledBack
-            ? Errors::writeFailed($this->reason, $this->details, $this->rolledBackHint)
+            ? Errors::writeFailed($this->reason, $this->details, $this->rolledBackHint, $this->rolledBackState)
             : Errors::partialWrite(
                 $this->reason,
                 $this->postId,

src/Guides/GuideRepository.php

@@ -5,19 +5,55 @@ declare(strict_types=1);
 namespace LIT\MCP\Guides;
 
 /**
- * Reads guide markdown files from one directory. Topic names are restricted to
- * lowercase slugs, so no path outside the directory can ever be read.
+ * Guide topics: markdown files from one directory (the default), extended or overridden
+ * by the site via the filter `lit_mcp_guides` (spec §9.2), which returns
+ * array<string topic, string markdown>. Topic names are restricted to lowercase slugs,
+ * so no path outside the directory can ever be read; filter entries with another name or
+ * a non-string content are ignored. Filtered content is site-owned and returned as-is.
  */
 final class GuideRepository
 {
     private const TOPIC_PATTERN = '/^[a-z0-9]+(?:-[a-z0-9]+)*$/';
 
+    /** @var array<string, string>|null Filtered topics, read once per instance (= request). */
+    private ?array $filtered = null;
+
     public function __construct(private string $directory)
     {
     }
 
     /** @return list<string> */
     public function topics(): array
+    {
+        $topics = array_unique(array_merge($this->fileTopics(), array_keys($this->filtered())));
+        sort($topics);
+
+        return array_values($topics);
+    }
+
+    public function get(string $topic): ?string
+    {
+        if (! self::isTopic($topic)) {
+            return null;
+        }
+
+        $filtered = $this->filtered();
+        if (array_key_exists($topic, $filtered)) {
+            return $filtered[$topic];
+        }
+
+        if (! in_array($topic, $this->fileTopics(), true)) {
+            return null;
+        }
+
+        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
+        $content = file_get_contents($this->directory . '/' . $topic . '.md');
+
+        return $content === false ? null : $content;
+    }
+
+    /** @return list<string> */
+    private function fileTopics(): array
     {
         $files = glob($this->directory . '/*.md');
         if ($files === false) {
@@ -27,25 +63,34 @@ final class GuideRepository
         $topics = [];
         foreach ($files as $file) {
             $topic = basename($file, '.md');
-            if (preg_match(self::TOPIC_PATTERN, $topic) === 1) {
+            if (self::isTopic($topic)) {
                 $topics[] = $topic;
             }
         }
-        sort($topics);
 
         return $topics;
     }
 
-    public function get(string $topic): ?string
+    /** @return array<string, string> */
+    private function filtered(): array
     {
-        if (preg_match(self::TOPIC_PATTERN, $topic) !== 1 || ! in_array($topic, $this->topics(), true)) {
-            return null;
+        if ($this->filtered !== null) {
+            return $this->filtered;
         }
 
-        $path = $this->directory . '/' . $topic . '.md';
-        // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
-        $content = file_get_contents($path);
+        $guides = apply_filters('lit_mcp_guides', []);
+        $this->filtered = [];
+        foreach (is_array($guides) ? $guides : [] as $topic => $markdown) {
+            if (is_string($topic) && self::isTopic($topic) && is_string($markdown)) {
+                $this->filtered[$topic] = $markdown;
+            }
+        }
 
-        return $content === false ? null : $content;
+        return $this->filtered;
+    }
+
+    private static function isTopic(string $topic): bool
+    {
+        return preg_match(self::TOPIC_PATTERN, $topic) === 1;
     }
 }

src/Integrations/WordPress/Content/ContentGetAbility.php

@@ -29,7 +29,7 @@ final class ContentGetAbility implements Ability
     {
         return 'Liest einen Eintrag vollständig: Kerndaten, Inhalt, Begriffe, alle Felder (Pods/Meta), '
             . 'Beitragsbild, rev (für lit-content-update). Bei Divi-Inhalten wird content nicht ausgegeben; '
-            . 'hints verweist dann auf lit-divi-outline.';
+            . 'hints erklärt dann, wie sie bearbeitet werden.';
     }
 
     public function inputSchema(): array

src/Integrations/WordPress/Content/ContentUpdateAbility.php

@@ -121,8 +121,7 @@ final class ContentUpdateAbility implements Ability
         if (array_key_exists('content', $input) && PostPresenter::usesDivi($post)) {
             return Errors::unsupported(
                 'Divi-Inhalte können nicht als Rohtext überschrieben werden; nichts wurde gespeichert.',
-                'Divi-Struktur über lit-divi-outline und die lit-divi-*-Tools bearbeiten; Titel, Auszug, '
-                    . 'Felder und Begriffe hier ohne content ändern.'
+                PostPresenter::DIVI_NOTE . ' Titel, Auszug, Felder und Begriffe hier ohne content ändern.'
             );
         }
 
@@ -235,7 +234,17 @@ final class ContentUpdateAbility implements Ability
 
         $detail = sprintf('Update of post %d failed: %s', $postId, $cause->getMessage());
         if ($failures === []) {
-            throw new WriteFailed(self::REASON, true, $postId, $revisionId, $cause, $detail);
+            throw new WriteFailed(
+                self::REASON,
+                true,
+                $postId,
+                $revisionId,
+                $cause,
+                $detail,
+                rolledBackState: $revisionId === null
+                    ? null
+                    : Errors::notSavedKeeping(sprintf('Revision %d', $revisionId))
+            );
         }
 
         $this->log->recordPartial(

src/Integrations/WordPress/Content/PostPresenter.php

@@ -16,10 +16,11 @@ use WP_Post;
  */
 class PostPresenter
 {
-    public const DIVI_HINT = 'Dieser Inhalt ist mit Divi gebaut. Die Divi-Struktur wird über lit-divi-outline '
-        . 'gelesen und mit den lit-divi-*-Tools bearbeitet; fehlen diese Tools, kann der Divi-Inhalt hier nicht '
-        . 'bearbeitet werden. content wird deshalb nicht ausgegeben; Titel, Auszug, Felder und Begriffe sind '
-        . 'über lit/content-update (direkt: lit-content-update) änderbar.';
+    public const DIVI_NOTE = 'Divi-Werkzeuge folgen in einer späteren Version; bis dahin im Divi-Builder bearbeiten.';
+
+    public const DIVI_HINT = 'Dieser Inhalt ist mit Divi gebaut; content wird deshalb nicht ausgegeben. '
+        . self::DIVI_NOTE . ' Titel, Auszug, Felder und Begriffe sind über lit/content-update '
+        . '(direkt: lit-content-update) änderbar.';
 
     public function __construct(private ContentSchema $schema)
     {

src/Integrations/WordPress/Menus/MenuAssignLocationAbility.php

@@ -13,8 +13,9 @@ use WP_Error;
 
 /**
  * lit/menu-assign-location: assigns a menu to a theme location (menu_id 0 removes
- * the assignment). Idempotent: assigning the same menu again, or removing an
- * already-empty location, changes nothing but still succeeds.
+ * the assignment – the menu then disappears from the site, so removing an existing
+ * assignment needs confirm: true). Idempotent: assigning the same menu again, or
+ * removing an already-empty location, changes nothing but still succeeds.
  */
 final class MenuAssignLocationAbility implements Ability
 {
@@ -34,7 +35,8 @@ final class MenuAssignLocationAbility implements Ability
 
     public function description(): string
     {
-        return 'Weist einer Theme-Position (siehe lit/menu-list) ein Menü zu; menu_id 0 entfernt die Zuweisung. '
+        return 'Weist einer Theme-Position (siehe lit/menu-list) ein Menü zu; menu_id 0 entfernt die Zuweisung '
+            . '(das Menü verschwindet dann von der Website; nur nach Rückfrage beim Nutzer mit confirm: true). '
             . 'Das vorher zugewiesene Menü steht in previous_menu_id.';
     }
 
@@ -45,6 +47,10 @@ final class MenuAssignLocationAbility implements Ability
             'properties' => [
                 'location' => ['type' => 'string', 'minLength' => 1],
                 'menu_id' => ['type' => 'integer', 'minimum' => 0],
+                'confirm' => [
+                    'type' => 'boolean',
+                    'description' => 'Nur nötig bei menu_id 0 (Zuweisung entfernen): true nach Bestätigung.',
+                ],
             ],
             'required' => ['location', 'menu_id'],
             'additionalProperties' => false,
@@ -90,12 +96,23 @@ final class MenuAssignLocationAbility implements Ability
         }
 
         $previous = MenuLocations::assigned()[$location] ?? 0;
+        $removed = $menuId === 0 && $previous > 0 ? self::menuLabel($previous) : null;
+        if ($removed !== null && ($input['confirm'] ?? false) !== true) {
+            return Errors::confirmRequired(sprintf(
+                'Menü %s von der Position %s entfernen? Es wird dort dann nicht mehr angezeigt.',
+                $removed,
+                $location
+            ));
+        }
+
         MenuLocations::assign($location, $menuId);
 
         $action = $menuId > 0 ? 'assigned' : 'unassigned';
-        $summary = $menuId > 0
-            ? sprintf('Menü %d der Position %s zugewiesen', $menuId, $location)
-            : sprintf('Zuweisung der Position %s entfernt', $location);
+        $summary = match (true) {
+            $menuId > 0 => sprintf('Menü %d der Position %s zugewiesen', $menuId, $location),
+            $removed !== null => sprintf('Menü %s von der Position %s entfernt', $removed, $location),
+            default => sprintf('Zuweisung der Position %s entfernt', $location),
+        };
 
         // The assignment is saved – a change log failure from here on is logged and reported as a warning only.
         $warnings = [];
@@ -113,4 +130,14 @@ final class MenuAssignLocationAbility implements Ability
             ->with('previous_menu_id', $previous > 0 ? $previous : null)
             ->toArray();
     }
+
+    /** '"Hauptmenü" (ID 3)', or just the ID when the menu itself no longer exists. */
+    private static function menuLabel(int $menuId): string
+    {
+        $menu = wp_get_nav_menu_object($menuId);
+
+        return is_object($menu)
+            ? sprintf('"%s" (ID %d)', $menu->name, $menuId)
+            : sprintf('(ID %d)', $menuId);
+    }
 }

src/Integrations/WordPress/Menus/MenuGetAbility.php

@@ -6,6 +6,7 @@ namespace LIT\MCP\Integrations\WordPress\Menus;
 
 use LIT\MCP\Abilities\Ability;
 use LIT\MCP\Abilities\Errors;
+use LIT\MCP\Abilities\Rev;
 use WP_Error;
 
 /**
@@ -29,7 +30,8 @@ final class MenuGetAbility implements Ability
         return 'Liefert ein Menü als Baum (id, title, type post/taxonomy/custom, object/object_id, url, '
             . 'children). object_id und url sind bei post/taxonomy-Einträgen nur informativ (WordPress leitet '
             . 'sie aus dem verlinkten Objekt ab); nur bei custom-Einträgen ist url maßgeblich. Der Baum kann '
-            . 'bearbeitet an lit/menu-set-items zurückgegeben werden.';
+            . 'bearbeitet an lit/menu-set-items zurückgegeben werden, zusammen mit menu_rev (Stand des Menüs, '
+            . 'damit parallele Änderungen nicht überschrieben werden).';
     }
 
     public function inputSchema(): array
@@ -51,8 +53,12 @@ final class MenuGetAbility implements Ability
                 'name' => ['type' => 'string'],
                 'locations' => ['type' => 'array', 'items' => ['type' => 'string']],
                 'items' => ['type' => 'array', 'items' => MenuTree::nodeSchema()],
+                'menu_rev' => [
+                    'type' => 'string',
+                    'description' => 'Stand des Menüs; Pflicht für lit/menu-set-items.',
+                ],
             ],
-            'required' => ['id', 'name', 'locations', 'items'],
+            'required' => ['id', 'name', 'locations', 'items', 'menu_rev'],
         ];
     }
 
@@ -82,12 +88,14 @@ final class MenuGetAbility implements Ability
         }
 
         $items = wp_get_nav_menu_items($menuId);
+        $items = is_array($items) ? $items : [];
 
         return [
             'id' => (int) $menu->term_id,
             'name' => (string) $menu->name,
             'locations' => MenuLocations::of((int) $menu->term_id),
-            'items' => MenuTree::build(is_array($items) ? $items : []),
+            'items' => MenuTree::build($items),
+            'menu_rev' => Rev::ofMenu($items),
         ];
     }
 }

src/Integrations/WordPress/Menus/MenuSetItemsAbility.php

@@ -7,6 +7,7 @@ namespace LIT\MCP\Integrations\WordPress\Menus;
 use LIT\MCP\Abilities\Ability;
 use LIT\MCP\Abilities\Errors;
 use LIT\MCP\Abilities\FollowUp;
+use LIT\MCP\Abilities\Rev;
 use LIT\MCP\Abilities\ToolResult;
 use LIT\MCP\Abilities\WriteFailed;
 use LIT\MCP\ChangeLog\ChangeLog;
@@ -17,7 +18,9 @@ use WP_Error;
  * as add/move/remove operations. Both run through one path: operations are applied to
  * the current tree (MenuOperations), the resulting tree is validated as a whole
  * (MenuWriter::plan) before anything is written, removals need confirm: true, and the
- * answer always carries previous_items so a mistake can be rebuilt. Write failures
+ * answer always carries previous_items so a mistake can be rebuilt. menu_rev (from
+ * lit/menu-get, Rev::ofMenu) is the optimistic lock: a menu changed since reading is
+ * refused with rev_mismatch before anything is planned or written. Write failures
  * surface as WriteFailed (lit_write_failed / lit_partial_write) from MenuWriter::apply.
  */
 final class MenuSetItemsAbility implements Ability
@@ -41,7 +44,9 @@ final class MenuSetItemsAbility implements Ability
 
     public function description(): string
     {
-        return 'Setzt die Einträge eines Menüs. Entweder items = vollständiger Zielbaum oder operations = Liste aus '
+        return 'Setzt die Einträge eines Menüs. menu_rev aus lit/menu-get ist Pflicht, damit parallele Änderungen '
+            . 'nicht überschrieben werden; die Antwort enthält die neue menu_rev. Entweder items = vollständiger '
+            . 'Zielbaum oder operations = Liste aus '
             . '{op: add, item, parent_id?, position?}, {op: move, id, parent_id?, position?}, {op: remove, id} '
             . '(Kinder eines entfernten Eintrags rücken an seine Stelle; position 0-basiert, ohne = ans Ende). '
             . 'Der Baum aus lit/menu-get kann bearbeitet unverändert zurückgegeben werden: bestehende Einträge '
@@ -67,6 +72,10 @@ final class MenuSetItemsAbility implements Ability
             'type' => 'object',
             'properties' => [
                 'menu_id' => ['type' => 'integer', 'minimum' => 1],
+                'menu_rev' => [
+                    'type' => 'string',
+                    'description' => 'menu_rev aus lit/menu-get (bzw. aus der letzten Antwort dieses Tools).',
+                ],
                 'items' => [
                     'type' => 'array',
                     'items' => ['type' => 'object'],
@@ -98,7 +107,7 @@ final class MenuSetItemsAbility implements Ability
                     'description' => 'Nur nötig, wenn Einträge entfernt werden.',
                 ],
             ],
-            'required' => ['menu_id'],
+            'required' => ['menu_id', 'menu_rev'],
             'additionalProperties' => false,
         ];
     }
@@ -107,7 +116,10 @@ final class MenuSetItemsAbility implements Ability
     {
         $tree = ['type' => 'array', 'items' => MenuTree::nodeSchema()];
 
-        return ToolResult::schema(['items' => $tree, 'previous_items' => $tree], ['items', 'previous_items']);
+        return ToolResult::schema(
+            ['items' => $tree, 'previous_items' => $tree, 'menu_rev' => ['type' => ['string', 'null']]],
+            ['items', 'previous_items', 'menu_rev']
+        );
     }
 
     public function annotations(): array
@@ -143,6 +155,13 @@ final class MenuSetItemsAbility implements Ability
         }
 
         $current = $this->currentItems($menuId);
+        if (($input['menu_rev'] ?? null) !== Rev::ofMenu(array_values($current))) {
+            return Errors::revMismatch(
+                'Das Menü wurde seit dem letzten Lesen geändert; nichts wurde geschrieben.',
+                'Mit lit/menu-get neu lesen und die Änderung auf dem aktuellen Stand (neue menu_rev) wiederholen.'
+            );
+        }
+
         $previous = MenuTree::build(array_values($current));
 
         $tree = array_key_exists('items', $input)
@@ -201,7 +220,7 @@ final class MenuSetItemsAbility implements Ability
             $warnings
         ) : null;
         $after = FollowUp::run(
-            fn () => MenuTree::build(array_values($this->currentItems($menuId))),
+            fn () => array_values($this->currentItems($menuId)),
             $this->name() . ' re-read',
             'Das Menü ist gespeichert, der neue Stand konnte aber nicht gelesen werden; mit lit/menu-get abrufen.',
             $warnings
@@ -215,8 +234,9 @@ final class MenuSetItemsAbility implements Ability
         return $result
             ->warnings($warnings)
             ->logId(is_int($logId) ? $logId : null)
-            ->with('items', is_array($after) ? $after : [])
+            ->with('items', is_array($after) ? MenuTree::build($after) : [])
             ->with('previous_items', $previous)
+            ->with('menu_rev', is_array($after) ? Rev::ofMenu($after) : null)
             ->toArray();
     }
 

src/Integrations/WordPress/PostGuard.php

@@ -16,6 +16,11 @@ use WP_Post;
  */
 final class PostGuard
 {
+    private const ZERO_DATE = '0000-00-00 00:00:00';
+
+    /** wp_insert_post() publishes a "future" post on save when its date is this close (MINUTE_IN_SECONDS). */
+    public const PUBLISH_WINDOW = 60;
+
     /**
      * Loads an entry the current user may edit. Trashed entries are refused (every write
      * on them would be surprising: publishing, scheduling or updating a trashed entry);
@@ -56,19 +61,26 @@ final class PostGuard
     }
 
     /**
-     * A scheduled entry whose publication time has passed (WordPress' cron missed it).
-     * wp_update_post() publishes such an entry on any save, so writes must not touch it.
+     * A scheduled entry whose publication time has passed (WordPress' cron missed it) or is
+     * less than a minute away: wp_insert_post() turns "future" into "publish" on any save when
+     * the date is within the next MINUTE_IN_SECONDS, so writes must not touch such an entry.
+     * A zero post_date_gmt (never set) falls back to the local post_date, like core does.
      */
     public static function missedSchedule(WP_Post $post): bool
     {
-        $gmt = (string) $post->post_date_gmt;
-        if ($post->post_status !== 'future' || $gmt === '' || $gmt === '0000-00-00 00:00:00') {
+        if ($post->post_status !== 'future') {
             return false;
         }
 
-        $time = strtotime($gmt . ' UTC');
+        $gmt = (string) $post->post_date_gmt;
+        if ($gmt === '' || $gmt === self::ZERO_DATE) {
+            $local = (string) $post->post_date;
+            $gmt = $local === '' || $local === self::ZERO_DATE ? '' : (string) get_gmt_from_date($local);
+        }
 
-        return $time !== false && $time <= time();
+        $time = $gmt === '' ? false : strtotime($gmt . ' UTC');
+
+        return $time !== false && $time <= time() + self::PUBLISH_WINDOW;
     }
 
     /**

src/Integrations/WordPress/Revisions/RevisionRestoreAbility.php

@@ -120,7 +120,12 @@ final class RevisionRestoreAbility implements Ability
         $backupId = RevisionPoint::capture($postId);
         $restored = wp_restore_post_revision((int) $revision->ID);
         if (! $restored) {
-            return Errors::writeFailed('WordPress konnte die Revision nicht wiederherstellen.');
+            return Errors::writeFailed(
+                'WordPress konnte die Revision nicht wiederherstellen.',
+                [],
+                null,
+                $backupId === null ? null : Errors::notSavedKeeping(sprintf('Revision %d', $backupId))
+            );
         }
 
         // The restore is saved – failures from here on are logged and reported as warnings only.

src/Integrations/WordPress/Status/PostReplaceWithCopyAbility.php

@@ -306,7 +306,8 @@ final class PostReplaceWithCopyAbility implements Ability
             $detail,
             null,
             null,
-            $details
+            $details,
+            rolledBackState: Errors::notSavedKeeping(sprintf('Sicherung %d im Papierkorb', $backupId))
         );
     }
 

src/Integrations/WordPress/Status/PostScheduleAbility.php

@@ -43,8 +43,8 @@ final class PostScheduleAbility implements Ability
     public function description(): string
     {
         return 'Plant die Veröffentlichung eines Eintrags zu einem Zeitpunkt in der Zukunft (Ortszeit der '
-            . 'Website). Ein bereits veröffentlichter Eintrag ist bis dahin offline. Nur auf ausdrücklichen '
-            . 'Wunsch des Nutzers verwenden.';
+            . 'Website). Ein bereits veröffentlichter Eintrag ist bis dahin offline; ein privater Eintrag wird '
+            . 'zum Zeitpunkt öffentlich. Nur auf ausdrücklichen Wunsch des Nutzers verwenden.';
     }
 
     public function inputSchema(): array
@@ -99,10 +99,11 @@ final class PostScheduleAbility implements Ability
             return Errors::invalidInput('Ungültiges Datum.', ['date' => 'Format JJJJ-MM-TT HH:MM erwartet']);
         }
 
-        if ($date->getTimestamp() <= time()) {
+        // Within PUBLISH_WINDOW WordPress would publish at once instead of scheduling.
+        if ($date->getTimestamp() <= time() + PostGuard::PUBLISH_WINDOW) {
             return Errors::invalidInput(
-                'Der Zeitpunkt muss in der Zukunft liegen.',
-                ['date' => 'liegt nicht in der Zukunft'],
+                'Der Zeitpunkt muss mindestens eine Minute in der Zukunft liegen.',
+                ['date' => 'liegt nicht (mindestens eine Minute) in der Zukunft'],
                 'Zum sofortigen Veröffentlichen lit/post-publish (direkt: lit-post-publish) verwenden.'
             );
         }
@@ -134,7 +135,15 @@ final class PostScheduleAbility implements Ability
         }
 
         // The status change is saved – failures from here on are logged and reported as warnings only.
-        $change = (new PostChangeResult($this->name(), $this->log, $postId))->afterSave($input, 'Planen');
+        $warnings = $post->post_status === 'private'
+            ? [sprintf(
+                'Der Eintrag war privat und wird am %s ÖFFENTLICH veröffentlicht; soll er privat bleiben, die Planung '
+                    . 'in WordPress zurücknehmen.',
+                $raw
+            )]
+            : [];
+        $change = (new PostChangeResult($this->name(), $this->log, $postId, 'die Änderung', $warnings))
+            ->afterSave($input, 'Planen');
         $title = (string) $post->post_title;
         $summary = sprintf('"%s" geplant für %s', $title, $raw)
             . ($post->post_status === 'publish' ? ' (war veröffentlicht und ist bis dahin offline)' : '');

src/Integrations/WordPress/Status/PostTrashAbility.php

@@ -16,7 +16,9 @@ use WP_Error;
 use WP_Post;
 
 /**
- * lit/post-trash: moves an entry to the trash – never a permanent delete. When the
+ * lit/post-trash: moves an entry to the trash – never a permanent delete. Trashing the
+ * static front page, the posts page or an entry linked in a menu is allowed but named in
+ * the confirmation question and as a warning in the result. When the
  * trash itself is disabled (EMPTY_TRASH_DAYS = 0), wp_trash_post() would delete the
  * entry permanently (wp-includes/post.php: `if ( ! EMPTY_TRASH_DAYS ) return
  * wp_delete_post( $post_id, true );`), so this tool refuses instead of calling it.
@@ -48,7 +50,8 @@ final class PostTrashAbility implements Ability
     public function description(): string
     {
         return 'Legt einen Eintrag in den Papierkorb (nie endgültig löschen; wiederherstellbar in WordPress). '
-            . 'Erst nach Rückfrage beim Nutzer mit confirm: true aufrufen.';
+            . 'Erst nach Rückfrage beim Nutzer mit confirm: true aufrufen. Ist der Eintrag Startseite, '
+            . 'Beitragsseite oder in Menüs verlinkt, nennen Rückfrage und warnings das.';
     }
 
     public function inputSchema(): array
@@ -96,7 +99,12 @@ final class PostTrashAbility implements Ability
         $postId = (int) $post->ID;
         $title = (string) $post->post_title;
         if (($input['confirm'] ?? false) !== true) {
-            return Errors::confirmRequired(sprintf('"%s" (ID %d) in den Papierkorb legen?', $title, $postId));
+            $impact = $post->post_status === 'trash' ? [] : $this->impact($post);
+
+            return Errors::confirmRequired(
+                trim(sprintf('"%s" (ID %d) in den Papierkorb legen? %s', $title, $postId, implode(' ', $impact))),
+                $impact === [] ? [] : ['warnings' => $impact]
+            );
         }
 
         if ($post->post_status === 'trash') {
@@ -113,6 +121,7 @@ final class PostTrashAbility implements Ability
             );
         }
 
+        $impact = $this->impact($post);
         $trashed = StatusWrite::run(
             static fn () => wp_trash_post($postId),
             $this->name(),
@@ -128,7 +137,7 @@ final class PostTrashAbility implements Ability
         }
 
         // The change is saved – a failure of the change log from here on is a warning only.
-        $change = (new PostChangeResult($this->name(), $this->log, $postId))
+        $change = (new PostChangeResult($this->name(), $this->log, $postId, 'die Änderung', $impact))
             ->log((string) $post->post_type, sprintf('"%s" in den Papierkorb gelegt', $title));
 
         $summary = sprintf('"%s" liegt im Papierkorb und ist dort wiederherstellbar.', $title);
@@ -138,6 +147,63 @@ final class PostTrashAbility implements Ability
             ->toArray();
     }
 
+    /**
+     * What visibly breaks when $post is in the trash: the static front page / posts page
+     * setting points to it, or menus link it (WordPress hides such menu items while the
+     * entry is trashed).
+     *
+     * @return list<string>
+     */
+    private function impact(WP_Post $post): array
+    {
+        $postId = (int) $post->ID;
+        $title = (string) $post->post_title;
+        $impact = [];
+        if (get_option('show_on_front') === 'page') {
+            if ((int) get_option('page_on_front') === $postId) {
+                $impact[] = sprintf(
+                    '"%s" ist als Startseite der Website eingestellt; im Papierkorb ist sie für Besucher nicht '
+                        . 'mehr erreichbar – unter Einstellungen → Lesen eine andere Startseite wählen.',
+                    $title
+                );
+            }
+
+            if ((int) get_option('page_for_posts') === $postId) {
+                $impact[] = sprintf(
+                    '"%s" ist als Beitragsseite der Website eingestellt; im Papierkorb ist die Beitragsübersicht '
+                        . 'nicht mehr erreichbar – unter Einstellungen → Lesen eine andere Beitragsseite wählen.',
+                    $title
+                );
+            }
+        }
+
+        $menus = $this->linkingMenus($postId);
+        if ($menus !== []) {
+            $impact[] = sprintf(
+                '"%s" ist in %s %s verlinkt; WordPress blendet diese Menüeinträge aus, solange der Eintrag im '
+                    . 'Papierkorb liegt.',
+                $title,
+                count($menus) === 1 ? 'dem Menü' : 'den Menüs',
+                implode(', ', array_map(static fn (string $name): string => '"' . $name . '"', $menus))
+            );
+        }
+
+        return $impact;
+    }
+
+    /** @return list<string> Names of the menus with an item linking $postId. */
+    private function linkingMenus(int $postId): array
+    {
+        $items = wp_get_associated_nav_menu_items($postId, 'post_type');
+        if (! is_array($items) || $items === []) {
+            return [];
+        }
+
+        $names = wp_get_object_terms(array_values($items), 'nav_menu', ['fields' => 'names']);
+
+        return is_array($names) ? array_values(array_unique(array_map('strval', $names))) : [];
+    }
+
     /** @param array<string, mixed> $input */
     private function load(array $input): WP_Post|WP_Error
     {