fix(psa): add TicketListResponseSchema response_model to search_tickets endpoint

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/api/endpoints/integrations.py

@@ -36,6 +36,7 @@ from app.schemas.psa_tickets import (
     PSATicketStatusUpdateSchema,
     TicketCreatePayloadSchema,
     PSAPrioritySchema,
+    TicketListResponseSchema,
 )
 import app.services.ticket_service as ticket_svc
 from app.services.psa.encryption import (
@@ -375,7 +376,7 @@ async def list_boards(
         return []
 
 
-@router.get("/tickets/search")
+@router.get("/tickets/search", response_model=TicketListResponseSchema)
 async def search_tickets(
     current_user: Annotated[User, Depends(require_engineer_or_admin)],
     db: Annotated[AsyncSession, Depends(get_db)],