BUG: GM Invis state needs to be tracked server side

[Jettford]

Make sure you've done the following:

• [X] I have checked that this issue has not already been reported.

• [X] I have validated that this issue is not a syntax error of either MySQL or SQLite.

• [X] I have pulled the latest version of the main branch of DarkflameServer and have confirmed that the issue exists there.

Issue Description

The GM Invis state can become desynced between the server and clients due to lack of state tracking

Reproduction steps

/gmlevel 9 - Become invisible
/gminvis - Toggle it off
/gmlevel 0 - Become GM Level 0 and it retoggles it

Expected Behavior

/gmlevel 0 should remove GM invis not just toggle it thoughtlessly.

Environment

Reproduceable on all platforms

[EmosewaMC]

Figured out how to actually do this finally. You need to save the current invisible state to the charxml under ghst with an attribute i which holds whether you are invisible or not.