Support customizable hotkeys in-application

[zkxs]

Presently changing hotkeys is supported internally and can be done via manual config file editing, but there is no way to do this in-app. Adding a hotkey binding GUI would be a moderate effort and would involve pulling in some pretty large dependencies, as making such a GUI with winit alone would be crazy. I'm not certain this feature is worth implementing, as dependency bloat is something I'm specifically trying to avoid in this application.

To gauge interest:

• react with 👍 if you want a hotkey rebinding UI and think the added bloat is worth it
• react with 👎 if you don't think the added bloat is worth it and can just cope with manually editing your config file