Implement desktop mode, custom resolution support, or adaptive resolution in scrcpy screen mirroring.

[x-legion]

Obtaining the current desktop resolution and running Scrcpy with that resolution should be straightforward. Adding a desktop icon to initiate desktop mode mirroring, as well as another for custom resolution, would be beneficial. Adaptive resolution would also be a valuable addition. Furthermore, capturing the current window resolution and initiating the Scrcpy video stream with that resolution would be useful.