Add MonitorAlbum component tests: 21 cases covering all flow diagrams (bufconn + testcontainers + hand-rolled mocks)

internal/server.go

@@ -29,6 +29,10 @@ func NewMusicAgregatorServer(cfg config.Config, riverClient *river.Client[pgx.Tx
 	}, nil
 }
 
+func NewMusicAgregatorServerWithService(service *MusicAgregatorService) *MusicAgregatorServer {
+	return &MusicAgregatorServer{service: service}
+}
+
 func (s *MusicAgregatorServer) GetArtists(ctx context.Context, req *pb.GetArtistsRequest) (*pb.GetArtistsResponse, error) {
 	return s.service.GetArtists(ctx, req)
 }