Force users to up-date in case their app version is no longer supported

[eylulnc]

To support upcoming breaking changes in the backend REST API structure, we need to implement a forced-update mechanism in the Android app. The app should send a version-check request to a new core endpoint at launch or when the Artemis instance is selected.

The server will return both the minimum supported version (minVersionAndroid).

If the current app version is below minVersionAndroid, the app must block access and display a forced update prompt with a link to the Google Play Store. This feature is crucial to ensure compatibility when communication-related endpoints are moved to a new prefix (/api/communication/...). Once implemented, this update mechanism should align with the backend changes and app release schedule to minimize downtime and unexpected errors for users.

Example:
https://artemis.tum.de/api/courses/377/conversations --> https://artemis.tum.de/api/communication/courses/377/conversations