Request: Option to change the shortcut keys

Is it possible to add an option for changing the shortcut keys? I started using FreeTube just a few days back, and I miss the {shift+.} and {shift+,} keys (as in youtube) to change the playback speed. Also, flashing the playback speed on the screen (when it is altered), would be very helpful.

Start by locating FreeTube's keyboard shortcut handling and the playback-speed controls. Confirm how the existing speed changes are triggered, then determine how configurable Shift+. and Shift+, bindings and an on-screen speed indicator should fit together. Done means both shortcuts work, users can change the bindings, and speed changes are visibly confirmed.

Written by the indexing model from the issue text.