feat: lit/content-create with Divi short form

New input divi (1-30 sections, short form like lit-divi-insert) builds a Divi 5
layout in one divi/placeholder. The whole description is checked before the
insert (Divi's map for "no entry yet"); the draft is inserted with its normal
WordPress fields only, then DiviContentComposer composes again bound to the new
entry and stores it via DiviSaver::saveNew (same kses window as save(), strict
DiviFlags). A refusal or failure deletes the draft. Result adds tree_rev and the
outline.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

tests/Unit/Integrations/WordPress/WordPressIntegrationTest.php

@@ -5,7 +5,9 @@ declare(strict_types=1);
 namespace LIT\MCP\Tests\Unit\Integrations\WordPress;
 
 use LIT\MCP\Abilities\Ability;
+use Brain\Monkey\Functions;
 use LIT\MCP\ChangeLog\ChangeLog;
+use LIT\MCP\Integrations\WordPress\Content\ContentComposer;
 use LIT\MCP\Integrations\WordPress\Schema\ContentSchema;
 use LIT\MCP\Integrations\WordPress\WordPressIntegration;
 use LIT\MCP\Tests\Unit\TestCase;
@@ -61,4 +63,23 @@ final class WordPressIntegrationTest extends TestCase
             self::assertMatchesRegularExpression('#^lit/[a-z]+(-[a-z]+)+$#', $ability->name());
         }
     }
+
+    public function testContentCreateGetsTheContentComposer(): void
+    {
+        Functions\when('get_post_type_object')->justReturn((object) ['cap' => (object) ['create_posts' => 'edit_pages']]);
+        Functions\when('current_user_can')->justReturn(true);
+        $schema = Mockery::mock(ContentSchema::class);
+        $schema->allows('isManaged')->andReturn(true);
+        $composer = Mockery::mock(ContentComposer::class);
+        $composer->expects('available')->andReturn(false);
+        $integration = new WordPressIntegration($schema, Mockery::mock(ChangeLog::class), $composer);
+
+        $create = array_values(array_filter(
+            $integration->abilities(),
+            static fn (Ability $ability): bool => $ability->name() === 'lit/content-create'
+        ))[0];
+        $result = $create->execute(['post_type' => 'page', 'title' => 'Start', 'divi' => [['type' => 'section']]]);
+
+        self::assertSame('lit_unsupported', $result->get_error_code());
+    }
 }