Ghosts now have (better) runechat (#95843)

## About The Pull Request

Ports our optimizations to the version of ghost runechat introduced by
https://github.com/tgstation/tgstation/pull/95223

Instead of looping through all the mobs a second time it will do it in
deadchat_broadcast(). Also adds a global for if drunechat is
enabled/disabled and an admin verb for toggling it on or off.

<details><summary>still works</summary>

<img width="330" height="220" alt="dreamseeker_kkNBPBjbMv"
src="https://github.com/user-attachments/assets/4706ad98-fafe-4f88-9de0-6b72983ab044"
/>

</details>

## Why It's Good For The Game

Better option for performance

## Changelog

🆑
code: speeds ghost runechat up a bit, and makes it show as italic
admin: adds a 'toggle dead runechat' admin verb in case you need to
disable it midround for an event or something
/🆑

code/modules/client/verbs/ooc.dm

@@ -133,7 +133,6 @@ GLOBAL_VAR_INIT(normal_ooc_colour, "#002eb8")
 	else
 		GLOB.dooc_allowed = !GLOB.dooc_allowed
 
-
 /client/proc/set_ooc()
 	set name = "Set Player OOC Color"
 	set desc = "Modifies player OOC Color"