As Vulkan crashes immediately on launch on a lot of Android devices (for around 15% of users that commented on the Android beta on Discord).
The previous usage of the OpenGL backend in the shortcuts was incorrect, as this backend is not strictly available on Android and the GLES backend should be used instead, as this is also what is displayed in the graphics settings.
Define shortcuts to launch the client with either Vulkan or OpenGL graphics backend, which can be accessed by long-pressing the app icon on the home screen. This feature is available for Android 7.1 and newer.
Restarting the client previously did not work, as the `shell_execute` function on Android uses `fork` which is not supported.
Now, the client is restarted by using an Android intent to restart the main activity. This is triggered by sending a user-defined message from the native code to the SDL main activity thread.
SDL automatically loads the libraries specified in the array returned by the `getLibraries` method, so loading it manually is unnecessary. SDL also has additional error handling to quit the app with an appropriate error message popup if the library could not be loaded, which was not handled previously.
