Fixes space syndis being unable to navigate space (#12405)

code/game/machinery/doors/airlock.dm

@@ -1191,8 +1191,8 @@ About the new airlock wires panel:
 	return 1
 
 /obj/machinery/door/airlock/CanAStarPass(obj/item/card/id/ID)
-//Airlock is passable if it is open (!density), bot has access, and is not bolted shut)
-	return !density || (check_access(ID) && !locked && arePowerSystemsOn())
+//Airlock is passable if it is open (!density), bot has access, and is not bolted or welded shut)
+	return !density || (check_access(ID) && !locked && !welded && arePowerSystemsOn())
 
 /obj/machinery/door/airlock/emag_act(mob/user)
 	if(!operating && density && arePowerSystemsOn() && !emagged)

code/modules/mob/living/simple_animal/hostile/syndicate.dm

@@ -116,7 +116,9 @@
 
 /mob/living/simple_animal/hostile/syndicate/melee/autogib/depot/Aggro()
 	. = ..()
-	if(target && istype(depotarea))
+	if(!istype(depotarea))
+		return
+	if(target)
 		if(!seen_enemy)
 			seen_enemy = TRUE
 			if(!ranged)
@@ -148,11 +150,13 @@
 
 /mob/living/simple_animal/hostile/syndicate/melee/autogib/depot/handle_automated_movement()
 	. = ..()
+	if(!istype(depotarea))
+		return
 	if(seen_enemy)
 		aggro_cycles++
 		if(alert_on_timeout && !raised_alert && aggro_cycles >= 60)
 			raise_alert("[name] has reported contact with hostile entity: [seen_enemy_name]")
-	if(scan_cycles >= 15 && istype(depotarea))
+	if(scan_cycles >= 15)
 		scan_cycles = 0
 		if(!atoms_share_level(src, spawn_turf))
 			if(istype(loc, /obj/structure/closet))
@@ -187,6 +191,8 @@
 		depotarea.increase_alert(reason)
 
 /mob/living/simple_animal/hostile/syndicate/melee/autogib/depot/death()
+	if(!istype(depotarea))
+		return ..()
 	if(alert_on_death)
 		if(seen_enemy_name)
 			raise_alert("[name] has died in combat with [seen_enemy_name].")
@@ -288,7 +294,7 @@
 	alert_on_spacing = FALSE
 
 /mob/living/simple_animal/hostile/syndicate/melee/autogib/depot/space/Process_Spacemove(var/movement_dir = 0)
-	return
+	return TRUE
 
 
 
@@ -302,7 +308,7 @@
 	loot = list(/obj/effect/mob_spawn/human/corpse/syndicatecommando, /obj/item/melee/energy/sword/saber/red, /obj/item/shield/energy)
 
 /mob/living/simple_animal/hostile/syndicate/melee/space/Process_Spacemove(var/movement_dir = 0)
-	return
+	return TRUE
 
 
 /mob/living/simple_animal/hostile/syndicate/ranged
@@ -326,7 +332,7 @@
 	loot = list(/obj/effect/mob_spawn/human/corpse/syndicatecommando, /obj/item/gun/projectile/automatic/c20r)
 
 /mob/living/simple_animal/hostile/syndicate/ranged/space/Process_Spacemove(var/movement_dir = 0)
-	return
+	return TRUE
 
 /mob/living/simple_animal/hostile/syndicate/ranged/space/autogib
 	loot = list()//gonna gibe, no loot.