Extract settings and harden geofence automation

lib/features/settings/models/geofence_system_state.dart

@@ -0,0 +1,17 @@
+enum GeofenceSystemIssue {
+  noActiveHome,
+  missingCoordinates,
+  locationServicesDisabled,
+  permissionDenied,
+  permissionDeniedForever,
+  backgroundPermissionRequired,
+  ready,
+}
+
+class GeofenceSystemState {
+  final GeofenceSystemIssue issue;
+
+  const GeofenceSystemState(this.issue);
+
+  bool get isReady => issue == GeofenceSystemIssue.ready;
+}