feat(watch): Wear OS companion app - UX surfaces + bridge client (#91-E, #91-F)

watch_app/lib/presentation/watch_session_app.dart

@@ -0,0 +1,38 @@
+import 'package:flutter/material.dart';
+
+import '../application/watch_session_view_model.dart';
+import 'watch_session_screen.dart';
+import 'watch_theme.dart';
+
+final class WatchSessionApp extends StatefulWidget {
+  const WatchSessionApp({super.key});
+
+  @override
+  State<WatchSessionApp> createState() => _WatchSessionAppState();
+}
+
+final class _WatchSessionAppState extends State<WatchSessionApp> {
+  late final WatchSessionViewModel _viewModel;
+
+  @override
+  void initState() {
+    super.initState();
+    _viewModel = WatchSessionViewModel();
+  }
+
+  @override
+  void dispose() {
+    _viewModel.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      debugShowCheckedModeBanner: false,
+      title: 'GameTime',
+      theme: watchTheme(),
+      home: WatchSessionScreen(viewModel: _viewModel),
+    );
+  }
+}