fix(lifecycle): propagate RepositoryName through PublishGitStatus

The agentctl WorkspaceTracker stamps every per-repo GitStatusUpdate
with RepositoryName, but the lifecycle PublishGitStatus translation
into GitEventPayload was dropping that field. The orchestrator then
forwarded a status with empty repository_name, the frontend store
routed everything into the empty-key bucket, and the Changes panel's
multi-repo grouping never triggered — no header, no per-repo split.

- GitStatusData gains RepositoryName (omitempty so single-repo
  payloads stay byte-identical on the wire).
- PublishGitStatus copies update.RepositoryName onto the payload.
- Test asserts the field survives the publish → subscribe round trip
  via the in-memory event bus on the GitEvent.<sessionID> subject.

Restart the agentctl process for any running multi-repo task to pick
up the new field; new launches get it automatically.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

apps/backend/internal/agent/lifecycle/event_types.go

@@ -225,6 +225,10 @@ type GitStatusData struct {
 	Files           interface{} `json:"files,omitempty"`
 	BranchAdditions int         `json:"branch_additions,omitempty"`
 	BranchDeletions int         `json:"branch_deletions,omitempty"`
+	// RepositoryName identifies which repository this status belongs to in
+	// multi-repo task workspaces. Empty for single-repo. Carried through to
+	// the frontend so the Changes panel can render per-repo group headers.
+	RepositoryName string `json:"repository_name,omitempty"`
 }
 
 type GitCommitData struct {

apps/backend/internal/agent/lifecycle/events.go

@@ -247,6 +247,7 @@ func (p *EventPublisher) PublishGitStatus(execution *AgentExecution, update *age
 			Files:           update.Files,
 			BranchAdditions: update.BranchAdditions,
 			BranchDeletions: update.BranchDeletions,
+			RepositoryName:  update.RepositoryName,
 		},
 	})
 }

apps/backend/internal/agent/lifecycle/events_git_status_test.go

@@ -0,0 +1,62 @@
+package lifecycle
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	agentctl "github.com/kandev/kandev/internal/agentctl/client"
+	"github.com/kandev/kandev/internal/common/logger"
+	"github.com/kandev/kandev/internal/events"
+	"github.com/kandev/kandev/internal/events/bus"
+)
+
+// Verifies the fix for "Changes panel shows no header / no existing changes".
+// agentctl tags every per-repo GitStatusUpdate with RepositoryName; that field
+// must survive the lifecycle PublishGitStatus translation so the orchestrator
+// (and thus the frontend) sees it.
+func TestPublishGitStatus_PropagatesRepositoryName(t *testing.T) {
+	log, _ := logger.NewLogger(logger.LoggingConfig{Level: "error", Format: "json"})
+	eventBus := bus.NewMemoryEventBus(log)
+	pub := NewEventPublisher(eventBus, log)
+
+	received := make(chan *bus.Event, 1)
+	subj := events.BuildGitEventSubject("sess-multi")
+	sub, err := eventBus.Subscribe(subj, func(_ context.Context, ev *bus.Event) error {
+		received <- ev
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("subscribe: %v", err)
+	}
+	defer func() { _ = sub.Unsubscribe() }()
+
+	exec := &AgentExecution{
+		ID:        "exec-1",
+		TaskID:    "task-1",
+		SessionID: "sess-multi",
+	}
+	pub.PublishGitStatus(exec, &agentctl.GitStatusUpdate{
+		Timestamp:      time.Now(),
+		RepositoryName: "frontend",
+		Branch:         "feature/x",
+		Modified:       []string{"src/app.tsx"},
+		Files:          map[string]agentctl.FileInfo{"src/app.tsx": {Path: "src/app.tsx"}},
+	})
+
+	select {
+	case ev := <-received:
+		payload, ok := ev.Data.(*GitEventPayload)
+		if !ok || payload == nil {
+			t.Fatalf("expected *GitEventPayload, got %T", ev.Data)
+		}
+		if payload.Status == nil {
+			t.Fatal("expected non-nil Status on payload")
+		}
+		if payload.Status.RepositoryName != "frontend" {
+			t.Errorf("repository_name was dropped: got %q", payload.Status.RepositoryName)
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("timed out waiting for git status event")
+	}
+}