feat(workspace): session-scoped Caller.Holder + ReleaseByHolder for ACP integration

internal/workspace/repository.go

@@ -58,6 +58,9 @@ type Repository interface {
 	TryStartPrune(ctx context.Context, id uuid.UUID) (*Worktree, error)
 	FinishPruneSuccess(ctx context.Context, id uuid.UUID) error
 	FinishPruneRollback(ctx context.Context, id uuid.UUID) error
+	// ReleaseWorktreesByHolder 一次性释放某 holder 持有的所有活跃 worktree。
+	// 用于 ACP 启动 reaper / supervisor.onExit 不知道具体 wtID 时的清理。
+	ReleaseWorktreesByHolder(ctx context.Context, holder string) ([]*Worktree, error)
 
 	// Workspace fetch (jobs runner)
 	ListFetchTargets(ctx context.Context) ([]FetchTarget, error)
@@ -403,6 +406,18 @@ func (r *pgRepo) FinishPruneRollback(ctx context.Context, id uuid.UUID) error {
 	return nil
 }
 
+func (r *pgRepo) ReleaseWorktreesByHolder(ctx context.Context, holder string) ([]*Worktree, error) {
+	rows, err := r.q.ReleaseWorktreesByHolder(ctx, &holder)
+	if err != nil {
+		return nil, errs.Wrap(err, errs.CodeInternal, "release worktrees by holder")
+	}
+	out := make([]*Worktree, 0, len(rows))
+	for _, row := range rows {
+		out = append(out, rowToWorktree(row))
+	}
+	return out, nil
+}
+
 // ===== Credential =====
 
 func rowToCredential(r workspacesqlc.GitCredential) *Credential {