audit #13: notification fix, sync guard, bypass gate, responsive layout, dynamic version, dart format, clock_display to backups, stats race fix, new locks, nginx swarm block

lib/logic/app_config.example.dart

@@ -46,4 +46,11 @@ abstract final class AppConfig {
 
   // ── AdMob ──────────────────────────────────────────────────────────────
   static const String adUnitId = 'ca-app-pub-0000000000000000/0000000000'; // REPLACE
+
+  // ── Debug ──────────────────────────────────────────────────────────────
+  /// When true, the client skips the real AdMob flow and sends a fake SSV
+  /// callback directly to the server (requires ADMOB_BYPASS=True server-side).
+  /// Set to false in production — the Dart compiler tree-shakes the bypass
+  /// code entirely when this is a compile-time constant false.
+  static const bool enableAdBypass = false;
 }