Update example build files

[andrew-bekhiet-solid]

Also adds missing internet access permissions to macos and android

[gemini-code-assist]

Code Review

This pull request updates the Android, iOS, macOS, and Web configurations for the Flutter example app, upgrading Gradle, Kotlin, Java, and platform deployment targets. However, several critical issues were identified in the changes: the specified Gradle version (8.14) and plugin versions (Android Gradle Plugin 8.11.1, Kotlin 2.2.20) do not exist and will cause build failures. Additionally, the iOS AppDelegate uses non-standard Flutter APIs (FlutterImplicitEngineDelegate and FlutterImplicitEngineBridge) that will result in compilation errors.

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