Add unit tests for player configurations and referral system

- Implement tests for player configuration creation, update, and deletion, ensuring proper handling of free and paid user scenarios.
- Add tests for referral registration, including valid and invalid referrer cases.
- Create tests for referral reward flow, verifying correct reward distribution and eligibility.
- Establish a test database setup with necessary schema for user, plan, payment, and notification models.
- Introduce helper functions for seeding test data and loading entities from the database.

internal/service/service_auth.go

@@ -38,10 +38,6 @@ func (s *appServices) Login(ctx context.Context, req *appv1.LoginRequest) (*appv
 		return nil, status.Error(codes.Unauthenticated, "Invalid credentials")
 	}
 
-	if err := s.issueSessionCookies(ctx, user); err != nil {
-		return nil, err
-	}
-
 	payload, err := buildUserPayload(ctx, s.db, user)
 	if err != nil {
 		return nil, status.Error(codes.Internal, "Failed to build user payload")
@@ -304,10 +300,6 @@ func (s *appServices) CompleteGoogleLogin(ctx context.Context, req *appv1.Comple
 		}
 	}
 
-	if err := s.issueSessionCookies(ctx, user); err != nil {
-		return nil, status.Error(codes.Internal, "session_failed")
-	}
-
 	payload, err := buildUserPayload(ctx, s.db, user)
 	if err != nil {
 		return nil, status.Error(codes.Internal, "Failed to build user payload")