V3-05: mounted (handlebar) mode

Wake lock via a WakelockController seam (mirrors LocationSource), gated strictly to actual recording and released on stop/discard/navigate-away/dispose. High-contrast ripprMountedTheme() applied only to the record screen. BigStat gained a scale param for the headline figure rather than a blanket TextTheme.apply, which crashes on Material 3's default theme.

test/config_test.dart

@@ -42,6 +42,19 @@ void main() {
     });
   });
 
+  group('mountedMode', () {
+    test('defaults to false', () async {
+      final config = await freshConfig();
+      expect(config.mountedMode, isFalse);
+    });
+
+    test('round-trips through set/get', () async {
+      final config = await freshConfig();
+      await config.setMountedMode(true);
+      expect(config.mountedMode, isTrue);
+    });
+  });
+
   group('uploadEndpoint', () {
     test('defaults to empty, not null or a placeholder', () async {
       final config = await freshConfig();