✨ Add ResolvesEntities concern for name-based ID resolution

- 🤖 Introduced `ResolvesEntities` trait to simplify entity resolution by name or ID across MCP tools.
- 📚 Updated tools (Meetups, Cities, Venues, Courses, Lecturers) to use the concern for resolving related entities (e.g., courses, venues, lecturers).
- 🎯 Enhanced tool descriptions and schemas for better name-based parameter handling with fallback support for IDs.
- ✅ Added dedicated feature tests for name resolution logic, partial matches, and error handling scenarios.

app/Mcp/Tools/MeetupEvent/ShowMyMeetupEventTool.php

@@ -40,7 +40,7 @@ class ShowMyMeetupEventTool extends Tool
     public function schema(JsonSchema $schema): array
     {
         return [
-            'id' => $schema->integer()->description('ID des Meetup-Termins.')->required(),
+            'id' => $schema->integer()->description('ID des Meetup-Termins (über list-my-meetup-events ermitteln; nicht den Nutzer danach fragen).')->required(),
         ];
     }
 }