chore(studio): bump editor lock to 0.2.1 (live status + fit-to-screen)

Pulls in:
 - Live step status on the graph during runs (the graph
   highlights running / done / failed / awaiting nodes
   alongside the run-tab list).
 - Empty-graph call-to-action overlay with an Add step
   button so the first opened-but-empty flow points the
   operator at the right action.
 - Fit-to-screen button + auto-fit on first open of each
   flow so wide flows aren't cut off in the default
   viewport.

Version 0.52.0 -> 0.52.1.

Signed-off-by: flemming-it <stefan.a.flemming@googlemail.com>

lib/main.dart

@@ -26,7 +26,7 @@ import 'widgets/widgets.dart';
 /// Studio's own build version. Bump on every UI commit so the
 /// running app self-identifies — visible in the sidebar header
 /// and quick-glance proof that you're seeing the current build.
-const String kStudioVersion = '0.52.0';
+const String kStudioVersion = '0.52.1';
 
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();