Fix modsuits and defibs (#93373)

## About The Pull Request

Fixes #93359

Caused by #93165

Inventory screen elements were no longer considered reachable, which
broke mousedrop handing on objects that check "is dragging into
inventory slot"

I don't know the best way to fix this yet but I figured the next best
thing would be to make all of these use the `drag_pickup` element, which
skips this reach-ability check

Thus I refactored it slightly to accommodate for items which should
contextually not be drag-pick-up-abble and bam, works like a charm

## Changelog

🆑 Melbert
fix: Dragging defibs and modsuits off your back works again
/🆑

---------

Co-authored-by: ArcaneMusic <41715314+ArcaneMusic@users.noreply.github.com>
Co-authored-by: Xander3359 <66163761+Xander3359@users.noreply.github.com>

code/modules/research/xenobiology/crossbreeding/_clothing.dm

@@ -113,22 +113,10 @@ Slimecrossing Armor
 	throw_speed = 1
 	throw_range = 3
 
-/obj/item/clothing/head/peaceflower/proc/at_peace_check(mob/user)
-	if(iscarbon(user))
-		var/mob/living/carbon/carbon_user = user
-		if(src == carbon_user.head)
-			to_chat(user, span_warning("You feel at peace. <b style='color:pink'>Why would you want anything else?</b>"))
-			return TRUE
-	return FALSE
-
-/obj/item/clothing/head/peaceflower/attack_hand(mob/user, list/modifiers)
-	if(at_peace_check(user))
-		return
-	return ..()
-
-/obj/item/clothing/head/peaceflower/mouse_drop_dragged(atom/over, mob/user, src_location, over_location, params)
-	if(at_peace_check(user))
-		return
+/obj/item/clothing/head/peaceflower/can_mob_unequip(mob/user)
+	if(user.get_item_by_slot(slot_flags) == src)
+		to_chat(user, span_warning("You feel at peace. <b style='color:pink'>Why would you want anything else?</b>"))
+		return FALSE
 	return ..()
 
 /obj/item/clothing/suit/armor/heavy/adamantine