Adds Sprites for Overmap Storm Severities (#3578)

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## About The Pull Request

Gives storms some visual differentiation from the minor/moderate/major
versions, adding some visual flavor and readability.


![image](https://github.com/user-attachments/assets/9d4ec565-d207-4a2b-9644-b4861788452f)

### Meteors:

![image](https://github.com/user-attachments/assets/9a10bb88-9908-4535-b9cb-b927ea4d0ab4)

### Electrical Storms:

![image](https://github.com/user-attachments/assets/0dabba78-eab6-4d86-bf01-7e59f055eda5)

### Carp Storms:

![image](https://github.com/user-attachments/assets/4f7cd59d-a934-4637-902f-f68a4ffc6a9c)


## Why It's Good For The Game

A ton of people have complained about not being able to pick apart
various storm severities, and this makes it pretty obvious which ones
will MURDER YOU AND YOUR CREW and which ones will pleasantly tickle your
hull

## Changelog

:cl:
fix: fallback sprite for dust storms was set to the carp sprite for some
reason.
imageadd: fancy new carp, meteor, and electrical storm
imagedel: old carp, meteor, and electrical storm sprites
/:cl:
(soul: taken out back and shot)

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the changes rather than a summary of the PR's contents. -->

code/modules/overmap/objects/event_datum.dm

@@ -41,7 +41,7 @@
 /datum/overmap/event/meteor
 	name = "asteroid field (moderate)"
 	desc = "An area of space rich with asteroids, going fast through here could prove dangerous"
-	token_icon_state = "meteor1"
+	token_icon_state = "meteor_moderate1"
 	chance_to_affect = 15
 	spread_chance = 50
 	chain_rate = 4
@@ -55,7 +55,15 @@
 
 /datum/overmap/event/meteor/Initialize(position, ...)
 	. = ..()
-	token.icon_state = "meteor[rand(1, 4)]"
+	switch(type) //woop! this picks one of two icon states for the severity of the storm in overmap.dmi
+		if(/datum/overmap/event/meteor/minor)
+			token.icon_state = "meteor_minor[rand(1, 2)]"
+		if(/datum/overmap/event/meteor)
+			token.icon_state = "meteor_moderate[rand(1, 2)]"
+		if(/datum/overmap/event/meteor/major)
+			token.icon_state = "meteor_major[rand(1, 2)]"
+		else
+			token.icon_state = "meteor_moderate1"
 	token.color = "#a08444"
 	token.light_color = "#a08444"
 	token.update_appearance()
@@ -133,7 +141,7 @@
 /datum/overmap/event/electric
 	name = "electrical storm (moderate)"
 	desc = "A spatial anomaly, an unfortunately common sight on the frontier. Disturbing it tends to lead to intense electrical discharges"
-	token_icon_state = "electrical1"
+	token_icon_state = "electrical_moderate1"
 	chance_to_affect = 15
 	spread_chance = 30
 	chain_rate = 3
@@ -143,7 +151,16 @@
 
 /datum/overmap/event/electric/Initialize(position, ...)
 	. = ..()
-	token.icon_state = "electrical[rand(1, 4)]"
+	switch(type) //woop! this picks one of two icon states for the severity of the storm in overmap.dmi
+		if(/datum/overmap/event/electric/minor)
+			token.icon_state = "electrical_minor[rand(1, 2)]"
+		if(/datum/overmap/event/electric)
+			token.icon_state = "electrical_moderate[rand(1, 2)]"
+		if(/datum/overmap/event/electric/major)
+			token.icon_state = "electrical_major[rand(1, 2)]"
+		else
+			token.icon_state = "electrical_moderate1"
+
 	token.color = "#e8e85c"
 	token.light_color = "#e8e85c"
 	token.update_appearance()
@@ -218,7 +235,7 @@
 /datum/overmap/event/meteor/carp
 	name = "carp migration (moderate)"
 	desc = "A migratory school of space carp. They travel at high speeds, and flying through them may cause them to impact your ship"
-	token_icon_state = "carp1"
+	token_icon_state = "carp_moderate1"
 	chance_to_affect = 15
 	spread_chance = 50
 	chain_rate = 4
@@ -230,15 +247,24 @@
 
 /datum/overmap/event/meteor/carp/Initialize(position, ...)
 	. = ..()
-	token.icon_state = "carp[rand(1, 4)]"
+	switch(type) //woop! this picks one of two icon states for the severity of the storm in overmap.dmi
+		if(/datum/overmap/event/meteor/carp/minor)
+			token.icon_state = "carp_minor[rand(1, 2)]"
+		if(/datum/overmap/event/meteor/carp)
+			token.icon_state = "carp_moderate[rand(1, 2)]"
+		if(/datum/overmap/event/meteor/carp/major)
+			token.icon_state = "carp_major[rand(1, 2)]"
+		else
+			token.icon_state = "carp_moderate1"
+
 	token.color = "#7b1ca8"
 	token.light_color = "#7b1ca8"
 	token.update_icon()
 
 
 /datum/overmap/event/meteor/carp/minor
 	name = "carp migration (minor)"
-	token_icon_state = "carp1"
+	token_icon_state = "carp_moderate1"
 	chance_to_affect = 5
 	spread_chance = 25
 	chain_rate = 4
@@ -249,7 +275,7 @@
 
 /datum/overmap/event/meteor/carp/major
 	name = "carp migration (major)"
-	token_icon_state = "carp1"
+	token_icon_state = "carp_moderate1"
 	chance_to_affect = 25
 	spread_chance = 25
 	chain_rate = 4
@@ -263,7 +289,7 @@
 /datum/overmap/event/meteor/dust
 	name = "dust cloud"
 	desc = "A cloud of spaceborne dust. Relatively harmless, unless you're travelling at relative speeds"
-	token_icon_state = "carp1"
+	token_icon_state = "dust1"
 	chance_to_affect = 30
 	spread_chance = 50
 	chain_rate = 4