Detaching the global-quick-tap functionality from the quick-tap term.
This makes way for two improvements:

1. This functionality can be added to combos under a unified name
   'global-quick-tap-ms'.

2. This allows users to set a lower term for the 'global-quick-tap'
   (typically ~100ms), and a higher term for the regular
   quick-tap (typically ~200ms)

This deprecates the global-quick-tap option, however if it is set, the
quick-tap-ms value will be copied to global-quick-tap-ms.

This brings the 'global-quick-tap' functionality to combos by filtering
out candidate combos that fell within their own quick tap term.

I also replaced `return 0` with `return ZMK_EV_EVENT_BUBBLE` where appropriate.
(I assume this was done in past as it is similar to errno returning, but
being that this is to signify an event type I find this more clear)

Co-authored-by: Cem Aksoylar <caksoylar@users.noreply.github.com>

Renaming global-quick-tap-ms to require-prior-idle.

Co-authored-by: Cem Aksoylar <caksoylar@users.noreply.github.com>