fix(security): honour Pods field restrictions (audit M4)

PodsFieldSource maps hidden, read_only, admin_only and
restrict_role/-capability like Pods' own view: hidden -> new status
HIDDEN, read_only -> READONLY, restricted and not permitted -> READONLY
with read_only_restricted, else HIDDEN. HIDDEN fields are not described,
read out, queried or written (they look unknown) but stay in the schema
for the media usage search; write() re-checks before Pods' save().
Required-but-restricted fields no longer block a create. Pods is not
active on DDEV: covered by unit tests with a field-option fixture.

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

tests/Unit/Integrations/WordPress/Content/PostPresenterTest.php

@@ -113,11 +113,14 @@ final class PostPresenterTest extends TestCase
         $password = new FieldDefinition('secret', 'Secret', 'password', 'pods', 'writable');
         $protected = new FieldDefinition('_internal', 'Internal', 'string', 'meta', 'readonly');
         $visible = new FieldDefinition('role', 'Funktion', 'string', 'pods', 'writable');
+        $restricted = new FieldDefinition('boss', 'Boss', 'string', 'pods', FieldDefinition::HIDDEN);
         $source = Mockery::mock(FieldSource::class);
         $source->expects('read')->once()->with(5, $visible)->andReturn('Leitung');
         $schema = Mockery::mock(ContentSchema::class);
         $schema->allows('taxonomies')->andReturn([]);
-        $schema->allows('fields')->andReturn(['secret' => $password, '_internal' => $protected, 'role' => $visible]);
+        $schema->allows('fields')->andReturn([
+            'secret' => $password, '_internal' => $protected, 'role' => $visible, 'boss' => $restricted,
+        ]);
         $schema->allows('sourceOf')->andReturn($source);
         $post = new WP_Post(['ID' => 5, 'post_type' => 'lit_person']);
 

tests/Unit/Integrations/WordPress/Schema/ContentSchemaTest.php

@@ -76,7 +76,10 @@ final class ContentSchemaTest extends TestCase
             (object) ['name' => 'post_format', 'show_ui' => false, 'hierarchical' => false, 'labels' => (object) ['name' => 'Formate']],
         ]);
         $schema = new ContentSchema(
-            [$this->source('meta', [new FieldDefinition('footnotes', 'footnotes', 'string', 'meta', 'writable')])],
+            [$this->source('meta', [
+                new FieldDefinition('footnotes', 'footnotes', 'string', 'meta', 'writable'),
+                new FieldDefinition('zz_hidden', 'Verborgen', 'string', 'pods', FieldDefinition::HIDDEN),
+            ])],
             static fn (string $type): bool => $type === 'page'
         );
 
@@ -92,6 +95,7 @@ final class ContentSchemaTest extends TestCase
         self::assertSame([['name' => 'category', 'label' => 'Kategorien', 'hierarchical' => true]], $withoutFields['taxonomies']);
         self::assertArrayNotHasKey('fields', $withoutFields);
         self::assertSame('footnotes', $withFields['fields'][0]['key']);
+        self::assertCount(1, $withFields['fields'], 'hidden (restricted) fields are not described (M4)');
         self::assertNull($schema->describe('et_pb_layout', false));
     }
 

tests/Unit/Integrations/WordPress/Schema/FieldValidatorTest.php

@@ -32,6 +32,7 @@ final class FieldValidatorTest extends TestCase
             'secret' => new FieldDefinition('_secret', '_secret', 'string', 'meta', 'readonly'),
             'city' => new FieldDefinition('city', 'city', 'unknown', 'sample', 'unknown'),
             'pin' => new FieldDefinition('pin', 'PIN', 'password', 'pods', 'writable'),
+            'boss' => new FieldDefinition('boss', 'Boss', 'string', 'pods', FieldDefinition::HIDDEN),
         ];
     }
 
@@ -72,8 +73,10 @@ final class FieldValidatorTest extends TestCase
             'mentor' => 7,
             'photos' => 3,
             'start' => '01.10.2026',
+            'boss' => 'x',
         ], false)['errors'];
 
+        self::assertSame($errors['nope'], $errors['boss'], 'a hidden field looks like an unknown one (M4)');
         self::assertStringContainsString('lit-content-types', $errors['nope']);
         self::assertSame('Feld ist schreibgeschützt.', $errors['secret']);
         self::assertSame('Erlaubte Werte: junior, senior.', $errors['level']);
@@ -123,4 +126,15 @@ final class FieldValidatorTest extends TestCase
         self::assertCount(1, $result['warnings']);
         self::assertStringContainsString('city', $result['warnings'][0]);
     }
+
+    /** M4: a required field the user cannot write (restricted Pods field) cannot block a create. */
+    public function testRequiredButRestrictedFieldsAreNotDemanded(): void
+    {
+        $definitions = [
+            'boss' => new FieldDefinition('boss', 'Boss', 'string', 'pods', FieldDefinition::HIDDEN, true),
+            'fixed' => new FieldDefinition('fixed', 'Fest', 'string', 'pods', FieldDefinition::READONLY, true),
+        ];
+
+        self::assertSame([], (new FieldValidator())->validate($definitions, [], true)['errors']);
+    }
 }