TGUI list conversions + bug fixes (#63354)

About The Pull Request

    Converts more inputs to TGUI. Possibly all user-facing input lists in the game.
    Did any surrounding text/number inputs as well
    Added null choice support so users can press cancel.
    Added some misc TGUI input fixes
    Fixed custom vendors while I was there

I refactored a lot of code while just poking around.
Primarily, usage of .len in files where I was already working on lists.
Some code was just awful - look at guardian.dm and its non use of early returns
If there are any disputes, I can revert it just fine, those changes are not integral to the PR.
Why It's Good For The Game

Fixes #63629
Fixes #63307
Fixes custom vendors /again/
Text input is more performant.
Part of a long series of TGUI conversion to make the game more visually appealing
Changelog

cl
refactor: The majority of user facing input lists have been converted to TGUI.
refactor: Tgui text inputs now scale with entered input.
fix: Many inputs now properly accept cancelling out of the menu.
fix: Fixes an edge case where users could not press enter on number inputs.
fix: Custom vendor bluescreen.
fix: You can now press ENTER on text inputs without an entry to cancel.
/cl

code/modules/assembly/doorcontrol.dm

@@ -14,10 +14,11 @@
 		. += span_notice("Its channel ID is '[id]'.")
 
 /obj/item/assembly/control/multitool_act(mob/living/user)
-	var/change_id = input("Set the shutters/blast door/blast door controllers ID. It must be a number between 1 and 100.", "ID", id) as num|null
-	if(change_id)
-		id = clamp(round(change_id, 1), 1, 100)
-		to_chat(user, span_notice("You change the ID to [id]."))
+	var/change_id = tgui_input_number(user, "Set the door controllers ID", "ID", id, 100, 1)
+	if(isnull(change_id))
+		return
+	id = round(change_id)
+	to_chat(user, span_notice("You change the ID to [id]."))
 
 /obj/item/assembly/control/activate()
 	var/openclose