Dashboard cards, backup last-seen

plugins/backups/api/routes.py

@@ -344,3 +344,19 @@ def _diffprojections(old, new):
             'aftertype': None if after is None else after[0],
         })
     return changes
+
+
+@backups_bp.route('/dashboard/stale', methods=['GET'])
+@jwt_required()
+@require_permission('backups.view')
+def dashboard_stale():
+    """Chains whose backup has stopped running.
+
+    Thin: the rule lives in services/staleness.py, where it is testable without
+    an auth layer in the way. Keyed on the last CONFIRMED check, never on the
+    last change - dedup means an unchanged config writes no revision, so a card
+    keyed on revision age would flag most of a healthy fleet.
+    """
+    from ..services.staleness import stalechains
+
+    return success_response(stalechains())