Ambience Buzz Handling Changes + Ambience buzz requires enviorment power (#84479)

## About The Pull Request
Partial port of https://github.com/DaedalusDock/daedalusdock/pull/996
- Fixes ambience prefrence inconsistancy issues with Observers unable to
turn off the ambience buzz.
- Ambience buzz requires a working, existing, charged APC with power to
the enviorment.
- Moves ``update_ambience_area()`` and ``refresh_looping_ambience()``
into ``code\controllers\subsystem\ambience.dm`` for better organization.

## Why It's Good For The Game

Mostly to tackle a prefrence bug where ghosts are unable to turn off
ambience buzz. But this also includes ambience buzz requiring a powered
area. Makes the station feel more dead when there's no enviorment power.
There should also be no buzzing inside space.

## Changelog

🆑 Kapu (ported by StrangeWeirdKitten)
fix: Ambience buzz will now respect ship ambience prefrences for
observers.
sound: Ambience buzz requires APC enviorment power to function
/🆑

---------

Co-authored-by: Ghom <42542238+Ghommie@users.noreply.github.com>

code/modules/mob/dead/observer/observer.dm

@@ -359,6 +359,12 @@ This is the proc mobs get to turn into a ghost. Forked from ghostize due to comp
 	abstract_move(destination) // move like the wind
 	return TRUE
 
+/mob/dead/observer/Moved(atom/old_loc, movement_dir, forced, list/old_locs, momentum_change)
+	. = ..()
+	var/area/new_area = get_area(src)
+	if(new_area != ambience_tracked_area)
+		update_ambience_area(new_area)
+
 /mob/dead/observer/verb/reenter_corpse()
 	set category = "Ghost"
 	set name = "Re-enter Corpse"