merge start signal

internal/store/store.go

@@ -773,8 +773,15 @@ func (s *Store) SetMergeTitle(ctx context.Context, id, title, actor string) erro
 
 func (s *Store) SetMergingBy(ctx context.Context, id, login string) error {
 	return s.write(ctx, func(tx *sql.Tx, emit emitFunc) error {
-		_, err := tx.ExecContext(ctx, `UPDATE tasks SET merging_by = ? WHERE id = ?`, login, id)
-		return err
+		projectID := ""
+		err := tx.QueryRowContext(ctx, `UPDATE tasks SET merging_by = ? WHERE id = ? RETURNING project_id`, login, id).Scan(&projectID)
+		if errors.Is(err, sql.ErrNoRows) {
+			return ErrNotFound
+		}
+		if err != nil {
+			return err
+		}
+		return emit(api.Event{Kind: "task.merge_started", ProjectId: &projectID, TaskId: &id, Actor: login, Payload: map[string]any{"id": id}})
 	})
 }