[REFACTOR] Consolidates SLOT_FLAG and SLOT_HUD into one ITEM_SLOT flag (#26743)

* IT WORKS UP UNTIL THIS POINT

* Consolidates SLOT_FLAG and SLOT_HUD into one

* Remove cover_both_ears

* SLOT_HUD to ITEM_SLOT

* Remove clothing_trait changes for the time being

* Remove accidental copy-paste

* Re-add no-slip var

* More failure to copy-paste correctly

* Leftover flag

* Combine left and right slot flags where possible

* UNGOOF MY DEFINES, PHAND IS NOT A THING

* Minor spacing changes

* Some more fixes from merge

* Seperates ITEM SLOT AMOUNT into two defines

* ON SECOND THOUGHT LETS NOT DO THAT.

* Addresses Contra's review

* Thank you GREP

* Rename ITEM_SLOT_FEET to ITEM_SLOT_SHOES

* Added a comment to the bitmasks in clothing defines

* Rename ITEM_SLOT_TIE to ITEM_SLOT_ACCESSORY

* These are for a seperate PR.

* Magboot fixes

* Requested changes

* Re-add accidental removal

* Wrong flags

* Update code/__DEFINES/clothing_defines.dm

Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>
Signed-off-by: Chap <erwin@lombok.demon.nl>

* Requested changes

* Merge fixes

* Fix double headset

* Fixes multiple accessories

---------

Signed-off-by: Chap <erwin@lombok.demon.nl>
Co-authored-by: Adrer <adrermail@gmail.com>
Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>

code/modules/customitems/item_defines.dm

@@ -150,7 +150,7 @@
 	force = 5
 	sharp = FALSE
 	flags = CONDUCT
-	slot_flags = SLOT_FLAG_BELT
+	slot_flags = ITEM_SLOT_BELT
 	throwforce = 5
 	w_class = WEIGHT_CLASS_NORMAL
 	attack_verb = list("attacked", "slashed", "stabbed", "sliced")
@@ -1555,7 +1555,7 @@
 	icon_state = "fethasnecklace"
 	item_state = "fethasnecklace"
 	item_color = "fethasnecklace"
-	slot_flags = SLOT_FLAG_MASK | SLOT_FLAG_TIE
+	slot_flags = ITEM_SLOT_MASK | ITEM_SLOT_ACCESSORY
 
 /// HugoLuman: Dan Martinez
 /obj/item/bedsheet/fluff/hugosheet
@@ -1613,7 +1613,7 @@
 		var/obj/item/clothing/head/helmet/space/plasmaman/lf53_fluff/F = new(P.loc)
 		if(P == H.head)
 			H.unEquip(P, TRUE, TRUE)
-			H.equip_to_slot(F, SLOT_HUD_HEAD, TRUE)
+			H.equip_to_slot(F, ITEM_SLOT_HEAD, TRUE)
 			H.update_inv_head()
 		qdel(P)
 
@@ -1689,7 +1689,7 @@
 	icon_state = "panzermedal"
 	item_state = "panzermedal"
 	item_color = "panzermedal"
-	slot_flags = SLOT_FLAG_TIE
+	slot_flags = ITEM_SLOT_ACCESSORY
 
 /// Sagrotter: Xann Zxiax
 /obj/item/clothing/accessory/medal/fluff/XannZxiax
@@ -1699,7 +1699,7 @@
 	icon_state = "Xann_necklace"
 	item_state = "Xann_necklace"
 	item_color = "Xann_necklace"
-	slot_flags = SLOT_FLAG_TIE
+	slot_flags = ITEM_SLOT_ACCESSORY
 
 /// Rb303: Isthel Eisenwald
 /obj/item/clothing/accessory/rbscarf