Oxygen is Toxic to the Vox, Plasma Heals Plasmamen, Plasmaman Suit Autoextinguishes, Oxygen Burns Plasmamen

Oxygen is toxic to the Vox (as toxic as plasma).
Plasma healing plasmaman from swindly @
https://github.com/tgstation/tgstation/pull/24209
Plasmaman suit auto-extinguishing actually does something now.
Oxygen burns Plasmamen.

code/modules/mob/living/carbon/human/life.dm

@@ -485,6 +485,8 @@
 	if(on_fire)
 		var/thermal_protection = get_thermal_protection()
 
+		if(wear_suit && wear_suit.flags & AUTOEXTINGUISH)
+			wear_suit.auto_extinguish(src)
 		if(thermal_protection >= FIRE_IMMUNITY_SUIT_MAX_TEMP_PROTECT)
 			return
 		if(thermal_protection >= FIRE_SUIT_MAX_TEMP_PROTECT)

code/modules/mob/living/carbon/human/species/plasmaman.dm

@@ -6,7 +6,7 @@
 	//language = "Clatter"
 	unarmed_type = /datum/unarmed_attack/punch
 
-	flags = IS_WHITELISTED | NO_BLOOD | NOTRANSSTING
+	flags = IS_WHITELISTED | NO_BLOOD | NOTRANSSTING | PLASMA_BASED
 	dietflags = DIET_OMNI
 	reagent_tag = PROCESS_ORG
 
@@ -15,6 +15,7 @@
 	butt_sprite = "plasma"
 
 	breath_type = "plasma"
+	poison_type = null
 
 	heat_level_1 = 350  // Heat damage level 1 above this point.
 	heat_level_2 = 400  // Heat damage level 2 above this point.