feat: Enhance TTS player functionality and UI

- Added resume functionality to TTS player when paused.
- Display voice name or language in TTS player UI.
- Improved error handling in reader provider with debug messages.
- Updated TTS service to configure Vietnamese voice and handle platform-specific audio settings.
- Removed wakelock dependency and related code.
- Fixed search screen error handling.
- Updated settings screen to navigate to home after sign out.
- Improved splash screen with timer management.
- Enhanced main app error handling with logging.
- Removed unused package_info_plus and wakelock_plus dependencies.
- Added environment variable support for mobile runtime.
- Integrated Google Sign-In configuration for Android.
- Created logging observer for Riverpod providers.
- Added scripts for environment setup and Google Sign-In validation.

lib/core/theme/app_theme.dart

@@ -16,4 +16,18 @@ class AppTheme {
       foregroundColor: Color(0xFF121826),
     ),
   );
+
+  static final ThemeData darkTheme = ThemeData(
+    useMaterial3: true,
+    colorScheme: ColorScheme.fromSeed(
+      seedColor: const Color(0xFF155DFC),
+      brightness: Brightness.dark,
+    ),
+    scaffoldBackgroundColor: const Color(0xFF0E1420),
+    appBarTheme: const AppBarTheme(
+      centerTitle: false,
+      backgroundColor: Color(0xFF0E1420),
+      foregroundColor: Color(0xFFE5EAF3),
+    ),
+  );
 }