feat: Add endpoint and service method to retrieve top users by various metrics

app/core/dependencies.py

@@ -9,6 +9,7 @@ from app.core.database import get_db
 from app.core.logging import get_logger
 from app.models.user import User
 from app.repositories.sound import SoundRepository
+from app.repositories.user import UserRepository
 from app.services.auth import AuthService
 from app.services.dashboard import DashboardService
 from app.services.oauth import OAuthService
@@ -193,4 +194,5 @@ async def get_dashboard_service(
 ) -> DashboardService:
     """Get the dashboard service."""
     sound_repository = SoundRepository(session)
-    return DashboardService(sound_repository)
+    user_repository = UserRepository(session)
+    return DashboardService(sound_repository, user_repository)