Update app icons and splash assets to match new branding, changing the
adaptive icon background color from light blue (#E6F4FE) to brand blue
(#0570F9) across all Android icon variants.
Add Metro configuration to resolve native-only React Native APIs with web-compatible shims. This enables packages like react-native-pager-view to work on the web platform by providing shim implementations for codegenNativeComponent, codegenNativeCommands, and CodegenTypes that are unavailable in react-native-web.
Also simplify Android signing configuration in CI by using standard Gradle property names (MYAPP_UPLOAD_*) and remove the build.gradle patching step.
