feat: change log tab with filters, revision links and clear button

ChangeLog gains query()/abilities()/clear() (filters: ability, user,
result, date range - all optional and additive). LogTab/LogListTable
render the "Protokoll" admin tab: WP_List_Table with pagination, links
to the post/attachment/nav_menu edit screen by object_type, a revision
link shown only when the user may edit the revision's parent post, and
a nonce+manage_options-gated "Protokoll leeren" with a JS confirmation
and highlighted 'partial' rows.

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

src/Admin/LogListTable.php

@@ -0,0 +1,150 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Admin;
+
+use LIT\MCP\ChangeLog\ChangeLog;
+use WP_Post;
+use WP_Term;
+
+// phpcs:disable PSR1.Methods.CamelCapsMethodName.NotCamelCaps -- method names are defined by WP_List_Table.
+
+/**
+ * List of change log entries (spec §8.3, ruling C5/Q13). WP_List_Table must be loaded
+ * before this file (LogTab::render() takes care of that).
+ */
+final class LogListTable extends \WP_List_Table
+{
+    private const PER_PAGE = 50;
+
+    /**
+     * @param array{
+     *     ability: string, user_id: int, result?: string, date_from?: string, date_to?: string
+     * } $filters
+     */
+    public function __construct(private ChangeLog $log, private array $filters)
+    {
+        parent::__construct(['singular' => 'lit_mcp_log_entry', 'plural' => 'lit_mcp_log_entries', 'ajax' => false]);
+    }
+
+    /** @return array<string, string> */
+    public function get_columns(): array
+    {
+        return [
+            'created_at' => __('Zeit (UTC)', 'wp-lit-mcp'),
+            'user' => __('Benutzer', 'wp-lit-mcp'),
+            'client' => __('Client', 'wp-lit-mcp'),
+            'ability' => __('Tool', 'wp-lit-mcp'),
+            'object' => __('Objekt', 'wp-lit-mcp'),
+            'summary' => __('Zusammenfassung', 'wp-lit-mcp'),
+            'revision' => __('Revision', 'wp-lit-mcp'),
+            'result' => __('Ergebnis', 'wp-lit-mcp'),
+        ];
+    }
+
+    public function prepare_items(): void
+    {
+        $page = max(1, (int) $this->get_pagenum());
+        $data = $this->log->query($this->filters, self::PER_PAGE, ($page - 1) * self::PER_PAGE);
+        $this->items = $data['rows'];
+        $this->_column_headers = [$this->get_columns(), [], []];
+        $this->set_pagination_args(['total_items' => $data['total'], 'per_page' => self::PER_PAGE]);
+    }
+
+    public function no_items(): void
+    {
+        esc_html_e('Keine Einträge.', 'wp-lit-mcp');
+    }
+
+    /**
+     * Highlights rows with result "partial" (a write that failed after an irreversible
+     * step, spec §2 principle 7/8.2) so admins notice them without reading every row.
+     *
+     * @param array<string, mixed> $item
+     */
+    public function single_row($item): void
+    {
+        $style = ($item['result'] ?? '') === 'partial' ? ' style="background:#fcf3e3;"' : '';
+        printf('<tr%s>', $style); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- fixed string.
+        $this->single_row_columns($item);
+        echo '</tr>';
+    }
+
+    /**
+     * @param array<string, mixed> $item
+     * @param string               $column_name
+     */
+    protected function column_default($item, $column_name): string
+    {
+        return match ($column_name) {
+            'user' => $this->userName((int) ($item['user_id'] ?? 0)),
+            'object' => $this->objectLink((string) ($item['object_type'] ?? ''), (string) ($item['object_id'] ?? '')),
+            'revision' => $this->revisionLink((int) ($item['revision_id'] ?? 0)),
+            default => esc_html((string) ($item[$column_name] ?? '')),
+        };
+    }
+
+    private function userName(int $userId): string
+    {
+        $user = get_userdata($userId);
+
+        return esc_html(is_object($user) ? (string) $user->display_name : '#' . $userId);
+    }
+
+    /**
+     * Links by object_type (ruling C5/Q13): known post types (not attachment) via
+     * get_edit_post_link(); attachment via the media edit screen; nav_menu (a term id)
+     * via the menus screen; settings/menu_location/anything else has no admin screen
+     * to link to and is shown as plain text.
+     */
+    private function objectLink(string $objectType, string $objectId): string
+    {
+        $label = trim($objectType . ' ' . $objectId);
+        $url = $objectId !== '' && ctype_digit($objectId) ? $this->urlFor($objectType, (int) $objectId) : '';
+
+        return $url !== '' ? sprintf('<a href="%s">%s</a>', esc_url($url), esc_html($label)) : esc_html($label);
+    }
+
+    private function urlFor(string $objectType, int $id): string
+    {
+        if ($objectType === 'attachment') {
+            return get_post($id) instanceof WP_Post ? admin_url('upload.php?item=' . $id) : '';
+        }
+
+        if ($objectType === 'nav_menu') {
+            return get_term($id, 'nav_menu') instanceof WP_Term ? admin_url('nav-menus.php?menu=' . $id) : '';
+        }
+
+        if ($objectType !== '' && post_type_exists($objectType)) {
+            $link = get_edit_post_link($id, 'raw');
+
+            return is_string($link) ? $link : '';
+        }
+
+        return '';
+    }
+
+    /**
+     * Only shown when the user could actually act on it: revision_id set and the
+     * revision's parent post is one the current user may edit (ruling C5/Q13).
+     */
+    private function revisionLink(int $revisionId): string
+    {
+        if ($revisionId <= 0) {
+            return '–';
+        }
+
+        $revision = get_post($revisionId);
+        $parentId = $revision instanceof WP_Post ? (int) $revision->post_parent : 0;
+        if ($parentId <= 0 || ! current_user_can('edit_post', $parentId)) {
+            return '–';
+        }
+
+        return sprintf(
+            '<a href="%s">%s</a>',
+            esc_url(admin_url('revision.php?revision=' . $revisionId)),
+            esc_html__('ansehen / wiederherstellen', 'wp-lit-mcp')
+        );
+    }
+}