[MIRROR] pai zmovement for climbing ladders, space and scaffolding (#10796)

Co-authored-by: Will <7099514+Willburd@users.noreply.github.com>
Co-authored-by: Kashargul <144968721+Kashargul@users.noreply.github.com>

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

@@ -103,6 +103,10 @@
 /mob/observer/dead/Initialize(mapload, aghost = FALSE)
 
 	appearance = loc
+	invisibility = initial(invisibility)
+	layer = initial(layer)
+	plane = initial(plane)
+	alpha = initial(alpha)
 	admin_ghosted = aghost
 
 	see_in_dark = world.view //I mean. I don't even know if byond has occlusion culling... but...

code/modules/mob/living/silicon/pai/pai_vr.dm

@@ -287,6 +287,12 @@
 /mob/living/silicon/pai/UnarmedAttack(atom/A, proximity_flag)
 	. = ..()
 
+	if(istype(A,/obj/structure/ladder))
+		// Zmovement already allows these to be used with the verbs anyway
+		var/obj/structure/ladder/L = A
+		L.attack_hand(src)
+		return
+
 	if(!ismob(A) || A == src)
 		return
 

code/modules/multiz/movement.dm

@@ -255,6 +255,16 @@
 		if(T.density)
 			return TRUE
 
+/mob/living/silicon/pai/can_ztravel()
+	if(incapacitated())
+		return FALSE
+
+	if(Process_Spacemove())
+		return TRUE
+
+	if(!restrained())
+		return TRUE
+
 // TODO - Leshana Experimental
 
 //Execution by grand piano!