coordinate rotation at harness turn boundaries

internal/herdr/adapter.go

@@ -13,6 +13,12 @@ type Adapter interface {
 	Kill(context.Context, Session) error
 	Occupancy(Session) (float64, error)
 }
+
+// TurnBoundary is optional so older herdr deployments remain usable. A true
+// result means the current harness turn has ended and handoff is safe.
+type TurnBoundary interface {
+	AtTurnBoundary(context.Context, Session) (bool, error)
+}
 type CLIAdapter struct {
 	Client  *Client
 	Harness string
@@ -43,6 +49,15 @@ func (a CLIAdapter) Release(ctx context.Context, s Session) (string, error) {
 func (a CLIAdapter) Kill(ctx context.Context, s Session) error {
 	return a.Client.Call(ctx, "pane.kill", s, nil)
 }
+func (a CLIAdapter) AtTurnBoundary(ctx context.Context, s Session) (bool, error) {
+	var r struct {
+		Status string `json:"status"`
+	}
+	if err := a.Client.Call(ctx, "pane.status", s, &r); err != nil {
+		return false, err
+	}
+	return !IsBusy(r.Status), nil
+}
 func (a CLIAdapter) Occupancy(s Session) (float64, error) {
 	if a.Usage == nil {
 		return 0, fmt.Errorf("adapter: usage reader required")

internal/orchestrator/orchestrator.go

@@ -165,6 +165,12 @@ func (c *Coordinator) rotate(ctx context.Context, hard float64) {
 		if err != nil || occupancy < hard {
 			continue
 		}
+		if boundary, ok := a.(herdr.TurnBoundary); ok {
+			atBoundary, boundaryErr := boundary.AtTurnBoundary(ctx, session)
+			if boundaryErr == nil && !atBoundary {
+				continue
+			}
+		}
 		ref, err := a.Release(ctx, session)
 		if err != nil {
 			continue

progress.md

@@ -67,6 +67,8 @@ Quota reporting now has strict payload validation, and `router.QuotaAvailability
 
 Notification delivery now supports Telegram and ntfy fan-out for completion, failure, block, and approval events, with event cursors, bounded polling, and notify-only surface policy preserved. Configure `ORCHESTRA_TELEGRAM_BOT_TOKEN`/`ORCHESTRA_TELEGRAM_CHAT_ID` or `ORCHESTRA_NTFY_TOPIC` to enable it.
 
+Rotation now honors an optional herdr turn-boundary probe (`pane.status`) before hard-threshold release. Adapters without the optional capability retain occupancy-based fallback behavior.
+
 Recommended order:
 
 1. Add the orchestration coordinator: lease → worktree → harness session → bootstrap → lifecycle events.