[scripts][combat-trainer] Use Firebase to store warhorn/egg data (2 of 2)

[MahtraDR]

Depends on #6672

Checks if a room has a warhorn/egg timer before using our warhorn or egg.

Allows multiple people to consecutively (or at least not in an overlapping manner) use their eggs/warhorns in the same room.

[vtcifer]

I don't see game instance data included in this or the other PR. Am I missing it or is it possible we'd get polluted data from DRF/DRX. And vice versa.

[MahtraDR]

I don't see game instance data included in this or the other PR. Am I missing it or is it possible we'd get polluted data from DRF/DRX. And vice versa.

Excellent point. Thank you. I can add a game instance check.

[MahtraDR]

I'm leaving this one to stew, because even with just the PR as is, with the limited testing it's getting, it's using up near enough data in our free Firebase plan to cause me to get a bill. Even if it's just a few dollars a month, I can't justify paying for this... I might well keep it as a private edit, but leaving it to stew longer.