Local network permission

[mboetger]

Android 17 adds a new runtime permission that affects dart sockets. This adds a page explaining how developers should handle this.

Partially addresses: #184859

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[gemini-code-assist]

Code Review

This pull request adds a new documentation page detailing how to declare and request Android local network permissions in Flutter when using Dart sockets, and updates the platform integration index and sidebar navigation. The review feedback suggests improving the Dart code example to avoid automatically calling openAppSettings() when permissions are permanently denied, as this can disrupt the user experience, and recommends advising developers to display an explanatory dialog first.

[flutter-website-bot]

Staged preview of the updated flutter.dev site (updated for commit 81c4cc3):

https://flutter-dev-230821--www-pr13795-local-network-permissi-etkz38ns.web.app

[sfshaza2]

lgtm