feat: persist tutorial completion and endless best score

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

lib/data/save_repository.dart

@@ -34,6 +34,11 @@ class SaveRepository {
           lastYmd: streak['lastYmd'] as String?,
         );
       }
+      _tutorialDone =
+          (json['flags'] as Map<String, dynamic>?)?['tutorialDone'] as bool? ??
+              false;
+      _endlessBest =
+          (json['endless'] as Map<String, dynamic>?)?['best'] as int? ?? 0;
     }
   }
 
@@ -45,8 +50,22 @@ class SaveRepository {
   final SharedPreferences _prefs;
   final Map<String, StageProgress> _progress = {};
   StreakState _streak = StreakState.initial;
+  bool _tutorialDone = false;
+  int _endlessBest = 0;
 
   StreakState get streak => _streak;
+  bool get tutorialDone => _tutorialDone;
+  int get endlessBest => _endlessBest;
+
+  Future<void> markTutorialDone() {
+    _tutorialDone = true;
+    return _flush();
+  }
+
+  Future<void> recordEndlessScore(int score) {
+    if (score > _endlessBest) _endlessBest = score;
+    return _flush();
+  }
 
   Future<void> saveStreak(StreakState streak) {
     _streak = streak;
@@ -111,6 +130,8 @@ class SaveRepository {
             'best': _streak.best,
             'lastYmd': _streak.lastYmd,
           },
+          'flags': {'tutorialDone': _tutorialDone},
+          'endless': {'best': _endlessBest},
         }),
       );
 }

test/data/save_repository_test.dart

@@ -67,4 +67,40 @@ void main() {
     expect(second.progressFor('season_001', 's1')!.stars, 3);
     expect(second.progressFor('season_001', 's1')!.bestScore, 777);
   });
+
+  group('tutorial flag and endless best', () {
+    test('defaults: tutorial not done, endless best 0', () async {
+      SharedPreferences.setMockInitialValues({});
+      final repo = SaveRepository(await SharedPreferences.getInstance());
+      expect(repo.tutorialDone, isFalse);
+      expect(repo.endlessBest, 0);
+    });
+
+    test('markTutorialDone persists across reload', () async {
+      SharedPreferences.setMockInitialValues({});
+      final prefs = await SharedPreferences.getInstance();
+      await SaveRepository(prefs).markTutorialDone();
+      expect(SaveRepository(prefs).tutorialDone, isTrue);
+    });
+
+    test('recordEndlessScore keeps the max', () async {
+      SharedPreferences.setMockInitialValues({});
+      final prefs = await SharedPreferences.getInstance();
+      final repo = SaveRepository(prefs);
+      await repo.recordEndlessScore(500);
+      await repo.recordEndlessScore(300);
+      expect(repo.endlessBest, 500);
+      expect(SaveRepository(prefs).endlessBest, 500);
+    });
+
+    test('legacy blob without new keys still loads', () async {
+      SharedPreferences.setMockInitialValues({
+        'save_v1':
+            '{"saveVersion":1,"progress":{},"streak":{"current":0,"best":0,"lastYmd":null}}',
+      });
+      final repo = SaveRepository(await SharedPreferences.getInstance());
+      expect(repo.tutorialDone, isFalse);
+      expect(repo.endlessBest, 0);
+    });
+  });
 }