Acid particles (+unsorted acid/burning/thermite component changes) (#75248)

This PR is way less than the file changes make it seem like it is.
Okay, first, the boring part:
- Picking up burning items is now a signal registered on the burning
component itself, instead of being a direct /obj/item/attack_hand()
check
- Sear sound now has an SFX define for convenience, since it is very
commonly used
- Fire stacks when extinguished on mobs will no longer clean acid on
items (WTF?)

code/game/objects/effects/particles/acid.dm

@@ -0,0 +1,15 @@
+// Acid related particles.
+/particles/acid
+	icon = 'icons/effects/particles/acid.dmi'
+	icon_state = list("goop_1" = 6, "goop_2" = 2, "goop_3" = 1)
+	width = 100
+	height = 100
+	count = 100
+	spawning = 0.5
+	color = "#FFFFFF80" //to get 96 alpha
+	lifespan = 1.5 SECONDS
+	fade = 1 SECONDS
+	grow = -0.025
+	gravity = list(0, 0.15)
+	position = generator(GEN_SPHERE, 0, 16, NORMAL_RAND)
+	spin = generator(GEN_NUM, -15, 15, NORMAL_RAND)

code/game/objects/effects/particles/fire.dm

@@ -1,21 +1,4 @@
 // Fire related particles.
-/particles/embers
-	icon = 'icons/effects/particles/generic.dmi'
-	icon_state = list("dot"=4,"cross"=1,"curl"=1)
-	width = 64
-	height = 96
-	count = 500
-	spawning = 5
-	lifespan = 3 SECONDS
-	fade = 1 SECONDS
-	color = 0
-	color_change = 0.05
-	gradient = list("#FBAF4D", "#FCE6B6", "#FD481C")
-	position = generator(GEN_BOX, list(-12,-16,0), list(12,16,0), NORMAL_RAND)
-	drift = generator(GEN_VECTOR, list(-0.1,0), list(0.1,0.025), UNIFORM_RAND)
-	spin = generator(GEN_NUM, list(-15,15), NORMAL_RAND)
-	scale = generator(GEN_VECTOR, list(0.5,0.5), list(2,2), NORMAL_RAND)
-
 /particles/bonfire
 	icon = 'icons/effects/particles/bonfire.dmi'
 	icon_state = "bonfire"
@@ -33,3 +16,20 @@
 	scale = generator(GEN_VECTOR, list(0.3, 0.3), list(1,1), NORMAL_RAND)
 	rotation = 30
 	spin = generator(GEN_NUM, -20, 20)
+
+/particles/embers
+	icon = 'icons/effects/particles/generic.dmi'
+	icon_state = list("dot" = 4,"cross" = 1,"curl" = 1)
+	width = 64
+	height = 96
+	count = 500
+	spawning = 5
+	lifespan = 3 SECONDS
+	fade = 1 SECONDS
+	color = 0
+	color_change = 0.05
+	gradient = list("#FBAF4D", "#FCE6B6", "#FD481C")
+	position = generator(GEN_BOX, list(-12,-16,0), list(12,16,0), NORMAL_RAND)
+	drift = generator(GEN_VECTOR, list(-0.1,0), list(0.1,0.025), UNIFORM_RAND)
+	spin = generator(GEN_NUM, list(-15,15), NORMAL_RAND)
+	scale = generator(GEN_VECTOR, list(0.5,0.5), list(2,2), NORMAL_RAND)

code/game/objects/effects/particles/misc.dm

@@ -1,4 +1,4 @@
-//general or un-matched particles, make a new file if a few can be sorted together.
+// General or un-matched particles, make a new file if a few can be sorted together.
 /particles/pollen
 	icon = 'icons/effects/particles/pollen.dmi'
 	icon_state = "pollen"