Add daily streak system and normalize bundle id to com.airkjw.blockseasons

Pure advanceStreak (1-day grace none, milestone flags at 3/7/14/30),
persisted in the save blob; StreakNotifier advances on every finished
attempt; home screen flame chip and milestone snackbar. Fix flutter
create's camelCased iOS bundle id and underscored Android application
id to the agreed lowercase form before any store registration.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/state/streak_notifier.dart

@@ -0,0 +1,16 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+import '../data/streak.dart';
+import 'providers.dart';
+
+/// Daily streak state; advanced once per stage attempt (win or lose).
+class StreakNotifier extends Notifier<StreakState> {
+  @override
+  StreakState build() => ref.read(saveRepositoryProvider).streak;
+
+  Future<void> onStagePlayed(DateTime now) async {
+    final next = advanceStreak(state, now);
+    await ref.read(saveRepositoryProvider).saveStreak(next);
+    state = next;
+  }
+}