[Developer] #204 Phase 1 MVP — Flutter app skeleton complete

- Drift 21 tables (8 catalog + 11 user + habit_dose_variants + meta_kv)
  with R1~R10 CHECK constraints and 19 indexes
- 8 hand-crafted seed JSON catalogs in app/assets/seed/
  (refs 84, protocols 34, methodologies 21, frame_patterns 30,
   reward_menu_items 30, break_protocols 8, common_frames 5, diet_patterns 5)
- 6 domain functions: recommend_variant, compute_streak,
  validate_frame_level, active_habit_quota, weekly_minimum_ratio,
  seed_importer (transactional, idempotent)
- 4 vertical-slice Riverpod screens: HabitList, HabitCreate, CheckIn, Streak
- 31 unit tests passing; flutter analyze clean
- OQ-5 streak semantics: missing entry ≠ explicit blank
  (missing = end of history; only TrackerValue.blank triggers Never-miss-twice)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/lib/main.dart

@@ -0,0 +1,30 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+import 'state/providers.dart';
+import 'ui/screens/habit_list_screen.dart';
+
+Future<void> main() async {
+  WidgetsFlutterBinding.ensureInitialized();
+  final db = await openProductionDatabase();
+  runApp(ProviderScope(
+    overrides: [appDatabaseProvider.overrideWithValue(db)],
+    child: const LifeHelperApp(),
+  ));
+}
+
+class LifeHelperApp extends StatelessWidget {
+  const LifeHelperApp({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'life-helper',
+      theme: ThemeData(
+        colorScheme: ColorScheme.fromSeed(seedColor: Colors.indigo),
+        useMaterial3: true,
+      ),
+      home: const HabitListScreen(),
+    );
+  }
+}