refactors climbing into an element (#55978)

Co-authored-by: Fikou <piotrbryla@onet.pl>
Co-authored-by: Ghom <42542238+Ghommie@users.noreply.github.com>
Co-authored-by: Mothblocks <35135081+Jared-Fogle@users.noreply.github.com>

code/game/objects/structures/transit_tubes/transit_tube.dm

@@ -7,7 +7,6 @@
 	density = TRUE
 	layer = LOW_ITEM_LAYER
 	anchored = TRUE
-	climbable = TRUE
 	pass_flags_self = PASSGLASS
 	var/tube_construction = /obj/structure/c_transit_tube
 	var/list/tube_dirs //list of directions this tube section can connect to.
@@ -20,6 +19,7 @@
 		setDir(newdirection)
 	init_tube_dirs()
 	generate_tube_overlays()
+	AddElement(/datum/element/climbable)
 
 /obj/structure/transit_tube/Destroy()
 	for(var/obj/structure/transit_tube_pod/P in loc)