Makes PKA bulky and also fixes a runtime (shiptest-ss13#2174)

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## About The Pull Request
see title
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documented or this can delay review and even discourage maintainers from
merging your PR! -->

## Why It's Good For The Game
you can no longer carry the Infinite Ammo Gun in your backpack
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benefit the game. If you can't justify it in words, it might not be
worth adding. -->

## Changelog

:cl:
balance: PKAs are now bulky
/:cl:

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code/modules/jobs/job_types/shaft_miner.dm

@@ -56,8 +56,8 @@
 		/obj/item/kitchen/knife/combat/survival=1,
 		/obj/item/mining_voucher=1,
 		/obj/item/mining_scanner=1,
-		/obj/item/gun/energy/kinetic_accelerator=1,\
 		/obj/item/stack/marker_beacon/ten=1)
+	belt = /obj/item/gun/energy/kinetic_accelerator
 
 /datum/outfit/job/miner/equipped/post_equip(mob/living/carbon/human/H, visualsOnly = FALSE)
 	..()
@@ -146,8 +146,8 @@
 		/obj/item/mining_scanner=1,
 		/obj/item/reagent_containers/hypospray/medipen/survival,
 		/obj/item/reagent_containers/hypospray/medipen/survival,\
-		/obj/item/gun/energy/kinetic_accelerator/old=1,\
 		/obj/item/stack/marker_beacon/ten=1)
+	belt = /obj/item/gun/energy/kinetic_accelerator/old
 
 /datum/outfit/job/miner/righand
 	name = "Righand"

code/modules/mining/mine_items.dm

@@ -58,7 +58,7 @@
 	new /obj/item/storage/bag/ore(src)
 	new /obj/item/mining_scanner(src)
 	new /obj/item/gun/energy/kinetic_accelerator(src)
-	new /obj/item/clothing/glasses/meson/prescription(src) //WS edit - Prescription HUDs
+	new /obj/item/clothing/glasses/meson/prescription(src)
 	new /obj/item/clothing/glasses/meson(src)
 	new /obj/item/survivalcapsule(src)
 	new /obj/item/clothing/head/hardhat/mining(src)

code/modules/mob/living/simple_animal/hostile/mining_mobs/hivelord.dm

@@ -441,7 +441,8 @@
 						/obj/item/pickaxe = 8,
 						/obj/item/pickaxe/mini = 4,
 						/obj/item/pickaxe/silver = 2,
-						/obj/item/pickaxe/diamond = 1
+						/obj/item/pickaxe/diamond = 1,
+						/obj/item/gun/energy/kinetic_accelerator = 1
 						)
 					)
 				else
@@ -542,8 +543,6 @@
 							)
 						)
 					)
-				if(prob(30))
-					backpack_contents += /obj/item/gun/energy/kinetic_accelerator
 			else
 				back = /obj/item/kinetic_crusher
 		if("Oldminer")
@@ -625,12 +624,10 @@
 							)
 						)
 					)
-				if(prob(30))
-					backpack_contents += /obj/item/gun/energy/kinetic_accelerator/old
 			else
 				back = /obj/item/kinetic_crusher/old
 			if(prob(30))
-				belt = /obj/item/storage/belt/mining/alt
+				belt = /obj/item/gun/energy/kinetic_accelerator/old
 			if(prob(30))
 				r_pocket = pickweight(list(
 					/obj/item/stack/marker_beacon = 20,

code/modules/projectiles/guns/energy/kinetic_accelerator.dm

@@ -15,8 +15,9 @@
 	can_bayonet = TRUE
 	knife_x_offset = 20
 	knife_y_offset = 12
-	internal_cell = TRUE //prevents you from giving it an OP cell - WS Edit
+	internal_cell = TRUE
 	custom_price = 750
+	w_class = WEIGHT_CLASS_BULKY
 	var/overheat_time = 16
 	var/holds_charge = FALSE
 	var/unique_frequency = FALSE // modified by KA modkits
@@ -238,6 +239,22 @@
 /obj/projectile/kinetic/mech
 	range = 5
 
+/obj/projectile/kinetic/mech/strike_thing(atom/target) //has no skill check for mechs
+	var/turf/target_turf = get_turf(target)
+	if(!target_turf)
+		target_turf = get_turf(src)
+	if(kinetic_gun)
+		var/list/mods = kinetic_gun.get_modkits()
+		for(var/obj/item/borg/upgrade/modkit/M in mods)
+			M.projectile_strike_predamage(src, target_turf, target, kinetic_gun)
+		for(var/obj/item/borg/upgrade/modkit/M in mods)
+			M.projectile_strike(src, target_turf, target, kinetic_gun)
+	if(ismineralturf(target_turf))
+		var/turf/closed/mineral/M = target_turf
+		M.gets_drilled(firer, TRUE)
+	var/obj/effect/temp_visual/kinetic_blast/K = new /obj/effect/temp_visual/kinetic_blast(target_turf)
+	K.color = color
+
 //Modkits
 /obj/item/borg/upgrade/modkit
 	name = "kinetic accelerator modification kit"