fix(protocol): carry approval id in push notifications

control.go

@@ -142,6 +142,7 @@ type PushNotifyPayload struct {
 	NavSessionID    string `json:"nav_session_id,omitempty"`
 	Type            string `json:"type"`
 	Summary         string `json:"summary"`
+	ApprovalID      string `json:"approval_id,omitempty"`
 	NotificationID  string `json:"notification_id,omitempty"`
 	TraceID         string `json:"trace_id,omitempty"`
 	CreatedAtUnixMS int64  `json:"created_at_unix_ms,omitempty"`

protocol_test.go

@@ -137,11 +137,39 @@ func TestPushNotifyPayloadBackwardCompatible(t *testing.T) {
 		t.Fatalf("legacy optional fields = id:%q trace:%q created:%d attempt:%d, want zero values",
 			got.NotificationID, got.TraceID, got.CreatedAtUnixMS, got.Attempt)
 	}
+	if got.ApprovalID != "" {
+		t.Fatalf("legacy ApprovalID = %q, want empty", got.ApprovalID)
+	}
 	if got.Type != "question" || got.Summary != "AgentD has a question" || got.NavSessionID != "agent-session-1" {
 		t.Fatalf("legacy payload decoded incorrectly: %+v", got)
 	}
 }
 
+func TestPushNotifyPayloadCarriesApprovalID(t *testing.T) {
+	t.Parallel()
+
+	payload := protocol.PushNotifyPayload{
+		NavSessionID: "agent-session-1",
+		Type:         "approval_request",
+		Summary:      "AgentD needs your approval",
+		ApprovalID:   "approval-123",
+	}
+	raw, err := json.Marshal(payload)
+	if err != nil {
+		t.Fatalf("marshal PushNotifyPayload: %v", err)
+	}
+	if !bytes.Contains(raw, []byte(`"approval_id":"approval-123"`)) {
+		t.Fatalf("PushNotifyPayload JSON = %s, want approval_id", raw)
+	}
+	var got protocol.PushNotifyPayload
+	if err := json.Unmarshal(raw, &got); err != nil {
+		t.Fatalf("unmarshal PushNotifyPayload: %v", err)
+	}
+	if got.ApprovalID != payload.ApprovalID {
+		t.Fatalf("ApprovalID = %q, want %q", got.ApprovalID, payload.ApprovalID)
+	}
+}
+
 func TestPushNotifyResultPayloadRoundtrip(t *testing.T) {
 	t.Parallel()