New Space Parallax (#2507)

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## About The Pull Request
Updates space parallax with new sprites, and fixes the mysterious black
pixels that would show up in parallax. This was happening because old
space sprites had a few transparent pixels in it. Hell.
Example:

![image](https://github.com/shiptest-ss13/Shiptest/assets/81882910/fe11f892-0404-4253-8845-6483ff0775c5)


## Changelog

:cl: Thgvr, PositiveEntropy
fix: Space will no longer have stray black pixels
imageadd: New space parallax by Imaginos
/:cl:

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code/_onclick/hud/parallax.dm

@@ -57,7 +57,7 @@
 			pref = PARALLAX_HIGH
 		switch(C.prefs.parallax)
 			if (PARALLAX_INSANE)
-				C.parallax_throttle = FALSE
+				C.parallax_throttle = PARALLAX_DELAY_DEFAULT
 				C.parallax_layers_max = 5
 				return TRUE
 
@@ -298,13 +298,6 @@
 	speed = 3
 	layer = 3
 
-/atom/movable/screen/parallax_layer/random/space_gas
-	icon_state = "space_gas"
-
-/atom/movable/screen/parallax_layer/random/space_gas/Initialize(mapload, view)
-	. = ..()
-	src.add_atom_colour(SSparallax.random_parallax_color, ADMIN_COLOUR_PRIORITY)
-
 /atom/movable/screen/parallax_layer/random/asteroids
 	icon_state = "asteroids"
 

code/controllers/subsystem/parallax.dm

@@ -8,14 +8,12 @@ SUBSYSTEM_DEF(parallax)
 	var/planet_x_offset = 128
 	var/planet_y_offset = 128
 	var/random_layer
-	var/random_parallax_color
 
 //These are cached per client so needs to be done asap so people joining at roundstart do not miss these.
 /datum/controller/subsystem/parallax/PreInit()
 	. = ..()
-	if(prob(70))	//70% chance to pick a special extra layer
-		random_layer = pick(/atom/movable/screen/parallax_layer/random/space_gas, /atom/movable/screen/parallax_layer/random/asteroids)
-		random_parallax_color = pick(COLOR_TEAL, COLOR_GREEN, COLOR_SILVER, COLOR_YELLOW, COLOR_CYAN, COLOR_ORANGE, COLOR_PURPLE)//Special color for random_layer1. Has to be done here so everyone sees the same color.
+	if(prob(20))	//20% chance to pick a special extra layer, in this case just asteroids, no space dirt
+		random_layer = /atom/movable/screen/parallax_layer/random/asteroids
 	planet_y_offset = rand(100, 160)
 	planet_x_offset = rand(100, 160)