REQ: add f_countdownstart

[blaps]

(Not sure this is the place to post this request, but let's try)

Missing a f_trigger that fires when countdown starts (not ends). I'd use it to automatically raise volume before game start.

Describe the solution you'd like add f_countdownstart as an unrestricted f_trigger.

Describe alternatives you've considered Maybe it should be an on_trigger instead. Not sure of the difference.

Another stab at it:

msg_trigger oncountdown "All players ready"
alias oncountdown "whatever you wanna do"

This works, except msg triggers are disabled in ruleset smackdown.

Additional context https://ezquake.com/docs/triggers.html

Impact on server or mods Not sure.

[riovv]

See pull req: https://github.com/QW-Group/ezquake-source/pull/1071