feat: lit/menu-create returns the new menu's menu_rev (trial)

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

tests/Unit/Integrations/WordPress/Menus/MenuCreateAbilityTest.php

@@ -44,11 +44,15 @@ final class MenuCreateAbilityTest extends TestCase
             'nav_menu_locations',
             ['footer-menu' => 2, 'primary-menu' => 8]
         );
+        Functions\expect('wp_get_nav_menu_items')->once()->with(8)->andReturn([]);
         $log = new FakeChangeLog(5);
 
         $result = (new MenuCreateAbility($log))->execute(['name' => 'Neu', 'location' => 'primary-menu']);
 
         self::assertSame(8, $result['menu_id']);
+        // Trial: the first lit/menu-set-items needs no lit/menu-get just for the lock.
+        self::assertSame(\LIT\MCP\Abilities\Rev::ofMenu([]), $result['menu_rev']);
+        self::assertContains('menu_rev', (new MenuCreateAbility($log))->outputSchema()['required']);
         self::assertSame('created', $result['changed'][0]['action']);
         self::assertSame(5, $result['log_id']);
         $log->assertRecorded([