Fixes for boulder processing machines (#96033)

## About The Pull Request
- Opening the panel of a boulder refiner machine or un-wrenching it now
turns off its environment light
- The boulder refiner machine has reagent holder of type
`/datum/reagents/plumbing` which fixes rounding errors & has other
plumbing optimized features
- The boulder refiner machine now only takes in booster reagents & only
outputs waste reagent. This means even if you have a tank with random
reagents attached to it, it will only take in booster reagents if
present & exclude the rest thus saving you time & space from taking in
other reagents
- booster reagents is now a static list shared by all machines thus
saving memory
- Removed `supply_offset` & `demand_offset` vars from core plumbing
component. These vars were making the pipes extend outside the tile
causing it to overlap with adjacent tile machine pipes making everything
ugly. Now the pipes are perpendicular to the conveyer belt sprite and
will only take in boulders from the conveyer belt direction


https://github.com/user-attachments/assets/5583a790-32b6-40df-a414-1602dd84fefd




- Map edited smelters so the conveyer belt is in the direction of the
refiner


## Changelog
🆑
fix: opening panel of boulder refinery with screwdriver or un-wrenching
it turns of its light
fix: boulder refinery only takes in booster reagents and excludes others
and only outputs waste chemicals as intended
fix: boulder refinery machines outputs waste reagents without rounding
errors in them
qol: removed conveyer sprite from boulder smelter & pixel shifts the
refiner so you can see it's plumbing pipes properly
sprite: smelters will now only take in boulders in the direction of its
conveyer belt. It's plumbing pipes are perpendicular to its conveyer
belt
/🆑

code/modules/mining/boulder_processing/_boulder_processing.dm

@@ -22,10 +22,6 @@
 	var/points_held = 0
 	///The action verb to display to players
 	var/action = "processing"
-
-
-	/// What list of reagents should we look at when we boost the effectiveness of this machinery? Assign a value to a chem as well, eg: /datum/reagent/water = 1 is a 10% boost
-	var/list/booster_list = list()
 	/// What reagent should be produced when a boost chemical is replaced by the booster_reagent?
 	var/datum/reagent/waste_chemical = /datum/reagent/water
 
@@ -107,6 +103,7 @@
 /obj/machinery/bouldertech/examine_more(mob/user)
 	. = ..()
 
+	var/list/datum/reagents/booster_list = get_booster_reagents()
 	if(length(booster_list))
 		. += span_notice("This machine's output is boosted by <b>chemical intake:</b><br>")
 		for(var/datum/reagent/increment as anything in booster_list)
@@ -121,7 +118,7 @@
 	icon_state ="[base_icon_state][suffix]"
 
 /obj/machinery/bouldertech/CanAllowThrough(atom/movable/mover, border_dir)
-	if(!anchored)
+	if(!anchored || !(dir == border_dir || dir == REVERSE_DIR(border_dir)))
 		return FALSE
 	if(istype(mover, /obj/item/stack/sheet))
 		return TRUE
@@ -254,6 +251,12 @@
 
 	refining_efficiency = initial(refining_efficiency) //Reset refining efficiency to 100%.
 
+///Returns a map of reagent -> boost amount to increase this machines efficiency
+/obj/machinery/bouldertech/proc/get_booster_reagents()
+	RETURN_TYPE(/list/datum/reagents)
+
+	return list()
+
 /**
  * Checks if this machine can process this material
  * Arguments
@@ -380,7 +383,7 @@
 			if(istype(chosen_boulder, /obj/item/boulder/artifact))
 				points_held = round((points_held + MINER_POINT_MULTIPLIER)) /// Artifacts give bonus points!
 			chosen_boulder.break_apart()
-			return//We've processed all the materials in the boulder, so we can just destroy it in break_apart.
+			return //We've processed all the materials in the boulder, so we can just destroy it in break_apart.
 
 		chosen_boulder.processed_by = src