Allow cheats to use modifier keys

[andrew-manger]

Is your feature request related to a problem? Please describe.
I would like to use navi to store tmux shortcuts but they all require using modifier keys.

Describe the solution you'd like
I'd like to write cheats that incorporate and press modifier keys to run commands

Example
% tmux

detach from session

ctrl+b, d

Describe alternatives you've considered
I can just store them in navi and not run them or use nb (or an equivalent knowledge base) to store them; however they would not be easily searchable.

[welcome]

Thanks for opening your first issue here! In case you're facing a bug, please update navi to the latest version first. Maybe the bug is already solved! :)