[MIRROR] Dynamic Human Icon Generation For Simple/Basic Mobs (& Cardboard Cutouts) [MDB IGNORE] (#18884)

* Dynamic Human Icon Generation For Simple/Basic Mobs (& Cardboard Cutouts) (#72517)

revive of #68760
this time a proc, not an element
this time supports cardboard cutouts
this time supports mob corpses

![image](https://user-images.githubusercontent.com/23585223/211064291-81070650-189f-4afa-8116-81b687e3ea35.png)

prevents these icons ever being outdated, they'll always look what they
are supposed to, saves spriting work

🆑 Fikou, a hood by Viro
refactor: humanoid mobs and cardboard cutouts automatically generate
their sprites, they no longer will be outdated
/🆑

Co-authored-by: Time-Green <timkoster1@hotmail.com>

* Modular!

* Fix signal override merge skew (#72882)

Caused by https://github.com/tgstation/tgstation/pull/72517, with
https://github.com/tgstation/tgstation/pull/72561 raising an error that
was being hidden before

This changes equip logic somewhat so that set_wearer was being called
twice.

I don't think this should be being run in visualsOnly at all, as it does
a ton of stuff like registering signals, updating UI, etc etc etc. Don't
have time to investigate further.

---------

Co-authored-by: Fikou <23585223+Fikou@users.noreply.github.com>
Co-authored-by: Time-Green <timkoster1@hotmail.com>
Co-authored-by: GoldenAlpharex <jerego1234@hotmail.com>
Co-authored-by: Mothblocks <35135081+Mothblocks@users.noreply.github.com>

code/game/objects/structures/chess.dm

@@ -4,7 +4,7 @@
 	icon = 'icons/obj/chess.dmi'
 	icon_state = "white_pawn"
 	name = "\improper Probably a White Pawn"
-	desc = "This is weird. Please inform adminstration on how you managed to get the parent chess piece. Thanks!"
+	desc = "This is weird. Please inform administration on how you managed to get the parent chess piece. Thanks!"
 	max_integrity = 100
 
 /obj/structure/chess/wrench_act(mob/user, obj/item/tool)
@@ -80,3 +80,28 @@
 	name = "\improper Black King"
 	desc = "A black king chess piece. It can move one tile in any direction."
 	icon_state = "black_king"
+
+/obj/structure/chess/checker
+	icon_state = "white_checker_man"
+	name = "\improper Probably a White Checker"
+	desc = "This is weird. Please inform administration on how you managed to get the parent checker piece. Thanks!"
+
+/obj/structure/chess/checker/whiteman
+	name = "\improper White Checker Man"
+	desc = "A white checker piece. Looks suspiciously like a flattened chess pawn."
+	icon_state = "white_checker_man"
+
+/obj/structure/chess/checker/whiteking
+	name = "\improper White Checker Man"
+	desc = "A white checker piece. It's stacked!"
+	icon_state = "white_checker_king"
+
+/obj/structure/chess/checker/blackman
+	name = "\improper Black Checker Man"
+	desc = "A black checker piece. Looks suspiciously like a flattened chess pawn."
+	icon_state = "black_checker_man"
+
+/obj/structure/chess/checker/blackking
+	name = "\improper Black Checker King"
+	desc = "A black checker piece. It's stacked!"
+	icon_state = "black_checker_king"