Mouse drop refactor (#20256)

Refactored mousedrag procs, added signals, some safeguards, did some
cleanups around, renamed them to make a little more sense. Mostly put in
line with TG's code.
Fast clicking and releasing with a drag, depending on the grace period
and how fast it is done, can be counted as clicks, to aid in combat
scenarios where you spamclick.

code/modules/detectivework/microscope/microscope.dm

@@ -174,9 +174,9 @@
 /obj/machinery/microscope/AltClick()
 	remove_sample(usr)
 
-/obj/machinery/microscope/MouseDrop(var/atom/other)
-	if(usr == other)
-		remove_sample(usr)
+/obj/machinery/microscope/mouse_drop_dragged(atom/over, mob/user, src_location, over_location, params)
+	if(over == user)
+		remove_sample(user)
 	else
 		return ..()