add fullscreen permission setting

[mahibi]

Add option for fullscreen permission in settings.

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Necessary that the call notification screen is shown without to unlock the phone.

I encountered the following behavior:

• USE_FULL_SCREEN_INTENT is granted when running via debug in Android Studio.

• It is not granted when building the app and running the apk. So the unlock screen is shown instead when a call comes in.

• However google play console has a setting to allow USE_FULL_SCREEN_INTENT by default for this app, as it is a call app. Hopefully this will work in v23.0.1 and USE_FULL_SCREEN_INTENT is granted when installed via Google Play.

The setting is especially useful for users who don't install via gplay.

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not needed
• 🔖 Capability is checked or not needed
• 🔙 Backport requests are created or not needed: /backport to stable-xx.x
• 📅 Milestone is set
• 🌸 PR title is meaningful (if it should be in the changelog: is it meaningful to users?)

[mahibi]

Created this PR when i was testing v23.0.1 and was wondering why the lockscreen still appeared despite of it being changed in 207f0a1.

[github-actions]

APK file: https://github.com/nextcloud/talk-android/actions/runs/24995504699/artifacts/6660911940
To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.
(please click on link to get QR code displayed)

[mahibi]

Tested with 23.0.1 and confirm USE_FULL_SCREEN_INTENT is granted by default via play store install.

Anyway we might have to use the fullscreen setting for the generic build (as the permission might not be granted by default when not installing via playstore).

[mahibi]

Also keep in mind when testing this with a fresh install via gplay: For the initial first time call the lockscreen may appear. This is not because of a missing fullscreen permission but for the other permissions that are required for the call. Only needs to be done one time when granting this for future uses.

[github-actions]

APK file: https://github.com/nextcloud/talk-android/actions/runs/25810919089/artifacts/6975388661
To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.
(please click on link to get QR code displayed)

[github-actions]

APK file: https://github.com/nextcloud/talk-android/actions/runs/25812682113/artifacts/6976322642
To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.
(please click on link to get QR code displayed)

[github-actions]

APK file: https://github.com/nextcloud/talk-android/actions/runs/25909117355/artifacts/7013971977
To test this change/fix you can simply download above APK file and install and test it in parallel to your existing Nextcloud app.
(please click on link to get QR code displayed)