Stage 4: guided Player for both Modes and the Session summary

- buildSegments lays a Plan out as holds with Transitions (get ready,
  switch sides, next round, next exercise) or sets with count-up Rests;
  Supersets alternate members and rest per round unless asked otherwise
- SessionRunner drives segments against an injected clock: auto-advance
  with a chime, pause, skip, back, rep sets confirmed with logged reps
  and kg, timed sets started on demand, early end
- Player screen: countdown ring, accent pulse in the last 3 s, Flip
  Animation, next-up cards, Rest Screen, mute toggle, screen kept on
- Sessions table (schema v2 migration) keeps a Plan snapshot and Set
  Logs; nothing is saved when no hold or set was done
- Summary with time, exercises or sets logged, and every Set Log
- Synthesised quiet cue sounds (tools/sounds), status bar per Mode

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/support/test_app.dart

@@ -6,7 +6,9 @@ import 'package:zenxercise/src/app.dart';
 import 'package:zenxercise/src/exercises/exercise.dart';
 import 'package:zenxercise/src/exercises/exercise_library.dart';
 import 'package:zenxercise/src/modes/mode.dart';
+import 'package:zenxercise/src/history/session_repository.dart';
 import 'package:zenxercise/src/plans/plan_repository.dart';
+import 'package:zenxercise/src/player/player_effects.dart';
 import 'package:zenxercise/src/settings/settings_controller.dart';
 
 import 'test_database.dart';
@@ -48,6 +50,18 @@ final sampleLibrary = ExerciseLibrary([
   exercise('Barbell_Squat', Mode.workout, primary: const ['quadriceps'], equipment: 'barbell'),
 ]);
 
+/// Counts chimes instead of playing them and leaves the screen alone.
+class FakePlayerEffects implements PlayerEffects {
+  final chimes = <Mode>[];
+  bool screenOn = false;
+
+  @override
+  Future<void> chime(Mode mode) async => chimes.add(mode);
+
+  @override
+  Future<void> keepScreenOn(bool on) async => screenOn = on;
+}
+
 /// A Pixel-sized screen instead of the default 800×600, so the floating
 /// navigation bar does not cover what a test taps.
 void usePhoneScreen(WidgetTester tester) {
@@ -62,6 +76,8 @@ Future<SettingsController> pumpApp(
   ExerciseLibrary? library,
   Map<String, Object> prefs = const {},
   PlanRepository? plans,
+  SessionRepository? sessions,
+  PlayerEffects? effects,
 }) async {
   SharedPreferences.setMockInitialValues(prefs);
   final settings = SettingsController(SettingsService());
@@ -74,6 +90,8 @@ Future<SettingsController> pumpApp(
         ChangeNotifierProvider.value(value: settings),
         Provider.value(value: library ?? sampleLibrary),
         Provider.value(value: plans ?? PlanRepository(db)),
+        Provider.value(value: sessions ?? SessionRepository(db)),
+        Provider<PlayerEffects>.value(value: effects ?? FakePlayerEffects()),
       ],
       child: const ZenXerciseApp(),
     ),