New bind flag to create submap agnostic binds

[Algos-hub]

This might be similar to spikespaz' request from earlier this year but,
after messing around with the submaps in my config lately and came up with a little annoyance:

bind = $mainMod, B, exec, $browser

bind = $mainMod, F, submap, focus

submap = focus

bind = $mainMod, B, exec, $browser
bind = $mainMod, H, movefocus, l
bind = $mainMod, J, movefocus, d
bind = $mainMod, K, movefocus, u
bind = $mainMod, L, movefocus, r

bind = $mainMod, escape, submap, reset

submap = reset

When in the default submap, pressing $mainMod + B works and will open the browser, however, as soon as I enter any submap it no longer works, and to make it work again, I would need to repeat the bind inside the submap, which can become quite annoying/difficult to configure/maintain if you have a lot of binds you want working across all submaps.

What I propose is a new bind flag that makes so the binds with those flags will work regardless of the submap you're currently in.

Choosing the letter a as an example, the section of code above would look like something like this:

binda = $mainMod, B, exec, $browser

bind = $mainMod, F, submap, focus

submap = focus

bind = $mainMod, H, movefocus, l
bind = $mainMod, J, movefocus, d
bind = $mainMod, K, movefocus, u
bind = $mainMod, L, movefocus, r

bind = $mainMod, escape, submap, reset

submap = reset

If, for instance, you have a submap for resizing windows, a submap for moving the focus between windows, and a submap for moving the focused window around, but still want to be able to go to any workspace using, for example, $mainMod + [0-9], it means you need to repeat those binds 4 times inside your config files, and having a bind flag that makes those binds work across any submap would most definitely help reducing this repetition.

[vaxerski]

#11818