✨ Add leader-based permissions to Meetup event tests and editable scope

- 🔒 Ensure leader users are required for Meetup event tests to simulate accurate permissions.
- ➕ Add `editableBy` scope to `MeetupEvent` model for consistent editable event handling.
- 🛠️ Refactor `mine` API endpoint and MCP tool to leverage `editableBy` scope.
- 🧪 Update tests to verify leader-based accessibility for Meetup events.

app/Mcp/Tools/MeetupEvent/ListMyMeetupEventsTool.php

@@ -12,7 +12,7 @@ use Laravel\Mcp\Server\Tool;
 use Laravel\Mcp\Server\Tools\Annotations\IsReadOnly;
 
 #[IsReadOnly]
-#[Description('Listet alle vom authentifizierten Nutzer erstellten Meetup-Termine, nach Startzeitpunkt absteigend sortiert.')]
+#[Description('Listet alle Meetup-Termine, die der authentifizierte Nutzer bearbeiten darf (selbst angelegt oder Leader des Meetups), nach Startzeitpunkt absteigend sortiert.')]
 class ListMyMeetupEventsTool extends Tool
 {
     public function handle(Request $request): Response
@@ -24,7 +24,7 @@ class ListMyMeetupEventsTool extends Tool
         }
 
         $meetupEvents = MeetupEvent::query()
-            ->where('created_by', $user->getAuthIdentifier())
+            ->editableBy((int) $user->getAuthIdentifier())
             ->orderByDesc('start')
             ->get();