refactor: update splash screen colors and remove Weblate configuration

- Changed the dark splash screen color in pubspec.yaml and styles.xml to #0B0E14 for better aesthetics.
- Removed the weblate.yaml file to streamline localization management and eliminate unused configurations.
- Updated background images for night mode in Android and iOS to ensure consistency across platforms.

android/app/src/main/res/values-night-v31/styles.xml

@@ -6,7 +6,7 @@
         <item name="android:windowFullscreen">false</item>
         <item name="android:windowDrawsSystemBarBackgrounds">false</item>
         <item name="android:windowLayoutInDisplayCutoutMode">shortEdges</item>
-        <item name="android:windowSplashScreenBackground">#000000</item>
+        <item name="android:windowSplashScreenBackground">#0B0E14</item>
     </style>
     <!-- Theme applied to the Android Window as soon as the process has started.
          This theme determines the color of the Android Window while your