feat(x11): implement X11 input capture backend

[posthum4n-ai]

We (Claude+me) got X11 input working using polling instead of mouse events. For me this works perfectly on X11, is this something we want into main? Tested with Gnome 46 + X11.

I don't have experience with Rust or X11, but I'm super happy with how this works for me.

[feschber]

Is there a good reason not to listen to mouse events rather than polling?
I'm not a huge fan of the "do something every 2ms" sort of thing.

Technically there should also be no reason to even spawn a separate thread (this is something I'm willing to accept and improve upon later)

[posthum4n-ai]

I agree because I hate polling too, I was under the impression that doing this event based was much harder (I assumed this because issues with X11 mouse events was the reason it wasn't implement for X11 yet).

I did notice an issue with log spam yesterday, that needs to be fixed first anyway (for myself at least :)

Separate thread probably is over-engineered, it kinda of made sense to me because it won't affect main thread/mouse responsiveness.

Because of the position polling method the cursor also needs to have offsets from border when re-entering a display.

Feel free to stash for now, I just wanted to show that it technically works with X11 (after switching back from Wayland), but not sure if it fits your application.

[posthum4n-ai]

I'll close it for now, okay.

[feschber]

I'm open to merging this and improving it later.
Its certainly much better than no backend at all. I just wanted to know your reasoning first.

[posthum4n-ai]

It's cool, I noticed another issue where my mouse got stuck, but I think that happened because of some weird glitch that duplicated my displays... Hopefully I can fix mainly the logging spam before I add or update this PR!