[READY] Atmos Refactor Part 7 (I think) - Kills signals + TGUIs stuff (#19867)

* I AM NOT A KING. I AM NOT A GOD. I AM LUNACY.

* THE SCOPE CREEP

* This was done in vi. No langserver. Send help.

* Progress

* Some issues fixed

* The code builds, but the maps dont

* CC builds, I doubt anything else does

* Do this now

* Safety

* The map compiles

* THE MAPPING HELL

* Airlock controllers dont work

* Fixed bombs

* AND THATS FIXED

* Phantom edit

* Restores LL I think

* The mapmerge hooks are actually retarded

* Fixes spawners

* Half working air control

* Picky

* Hyper efficient tank monitor

* Sanity

* Laying the framework

* Improved alert console

* Dont think this is actually done anywhere

* Metering

* ONE HUNDRED AND ~~EIGHTY~~ TWENTY SEVEN

* WE ARE READY FOR BOX TO BUILD

* One map done

* Well that was easy

* Another one

* I think this is done

* I should have removed this

* I would make a russian joke but <current event>

* Delta WIP

* Makes delta work

* Early review

* TM safeguard

* oops

* METAAAAAAAAAAAAAAAAAAAAAAAAA

* Fix #4213

* Trailing

* oh for piss sake

* Shutter fix

* Roundstart ATs can go away

* Review pass 1

* What could go wrong

* BOOM BOOM BOOM

* Not needed

* Fix seed vault

* Oops

* Review changes

code/game/objects/items/weapons/chrono_eraser.dm

@@ -243,6 +243,7 @@
 	return 0
 
 /obj/structure/chrono_field/return_air() //we always have nominal air and temperature
+	RETURN_TYPE(/datum/gas_mixture)
 	var/datum/gas_mixture/GM = new
 	GM.oxygen = MOLES_O2STANDARD
 	GM.nitrogen = MOLES_N2STANDARD

code/game/objects/items/weapons/explosives.dm

@@ -44,10 +44,6 @@
 		return
 	..()
 
-//assembly stuff
-/obj/item/grenade/plastic/receive_signal()
-	prime()
-
 /obj/item/grenade/plastic/Crossed(atom/movable/AM, oldloc)
 	if(nadeassembly)
 		nadeassembly.Crossed(AM, oldloc)

code/game/objects/items/weapons/grenades/chem_grenade.dm

@@ -229,10 +229,6 @@
 		to_chat(user, "<span class='notice'>You need to add an activation mechanism.</span>")
 		return TRUE
 
-//assembly stuff
-/obj/item/grenade/chem_grenade/receive_signal()
-	prime()
-
 /obj/item/grenade/chem_grenade/HasProximity(atom/movable/AM)
 	if(nadeassembly)
 		nadeassembly.HasProximity(AM)

code/game/objects/items/weapons/tanks/tanks.dm

@@ -209,6 +209,7 @@
 	return air_contents.remove(amount)
 
 /obj/item/tank/return_air()
+	RETURN_TYPE(/datum/gas_mixture)
 	return air_contents
 
 /obj/item/tank/assume_air(datum/gas_mixture/giver)