Various VV work and fixes (#19288)

Refactored various procs used by VV: Header generation, dropdown menu
generation, moved various things around, some defines.
Fixed VV to be able to edit associative lists.
Fixed VV to be able to make a list ex nihilo on a var.
Removed various dropdown menus that didn't exist anymore and were doing
nothing.
Fixed add verb option to not wipe the already existing verbs of the mob.
Fixed a runtime error on some lists view building that were not handled
correctly.
Fixed an issue with build mode not having the correct permissions for
devs.
Fixed an issue with editing a list referenced by a key in another list
via the edit referenced object option.
Added DF_VAR_EDITED flag.

code/modules/admin/admin_verbs.dm

@@ -744,7 +744,7 @@ var/list/admin_verbs_cciaa = list(
 	set name = "Toggle Build Mode Self"
 	set category = "Special Verbs"
 
-	if(!check_rights(R_ADMIN))
+	if(!check_rights(R_ADMIN|R_SPAWN))
 		return
 	var/datum/click_handler/handler = mob.GetClickHandler()
 	if(handler.type == /datum/click_handler/build_mode)