Adds Shrimp to Ocean Fishing (#5668)

## About The Pull Request
Does as the title suggests. Once this gets merged I'll work on making
some shrimp-based foods to go with the new crustacean.

The large icon for shrimp is made by Rootoo807 of Baystation12, and the
smaller aquarium shrimp icon is made by myself.

<img width="402" height="199" alt="image"
src="https://github.com/user-attachments/assets/23395718-eedc-4bec-a335-0fa35ea0c7fc"
/>

## Why It's Good For The Game
Shrimp are a pretty big meme in the Bubber community, and pretty
shrimply put, the April Fools shrimp species probably wouldn't make a
very good permanent addition. However, I feel this is a good compromise.
## Proof Of Testing
See below!
<details>
<summary>Screenshots/Videos</summary>


https://github.com/user-attachments/assets/bf897d0f-47c6-492b-96eb-4b93f7db33ef

<img width="462" height="390" alt="image"
src="https://github.com/user-attachments/assets/d4005154-fde6-4f3f-8bee-f81536a95b7e"
/>

</details>

## Changelog
🆑
add: Added a new crustacean to ocean fishing in the Fish-Porter 3000:
Shrimp!
/🆑

modular_zubbers/code/modules/fishing/fish/types/saltwater.dm

@@ -0,0 +1,21 @@
+/obj/item/fish/shrimp
+	name = "shrimp"
+	fish_id = "shrimp"
+	desc = "A reddish pink crustacean. How many of them would you have to eat for your skin to turn pink?"
+	icon = 'modular_zubbers/icons/obj/aquarium/fish.dmi'
+	icon_state = "shrimp"
+	dedicated_in_aquarium_icon = 'modular_zubbers/icons/obj/aquarium/fish.dmi'
+	dedicated_in_aquarium_icon_state = "shrimp_small"
+	sprite_width = 7
+	sprite_height = 7
+	average_size = 14
+	average_weight = 300
+	stable_population = 4
+	fish_traits = list()
+	required_temperature_min = MIN_AQUARIUM_TEMP
+	required_temperature_max = MIN_AQUARIUM_TEMP + 12
+	required_fluid_type = AQUARIUM_FLUID_SALTWATER
+	fillet_type = null
+
+/obj/item/fish/shrimp/get_fish_taste()
+	return list("raw shrimp" = 2)

modular_zubbers/code/modules/fishing/sources/subtypes/fishing_portal_machine.dm

@@ -0,0 +1,3 @@
+/datum/fish_source/portal/ocean/New()
+	fish_table += list(/obj/item/fish/shrimp = 5)
+	return ..()

tgstation.dme

@@ -9583,6 +9583,8 @@
 #include "modular_zubbers\code\modules\experisci\experiment\experiments.dm"
 #include "modular_zubbers\code\modules\experisci\experiment\handlers\experiment_handler.dm"
 #include "modular_zubbers\code\modules\experisci\experiment\types\scanning_fish.dm"
+#include "modular_zubbers\code\modules\fishing\fish\types\saltwater.dm"
+#include "modular_zubbers\code\modules\fishing\sources\subtypes\fishing_portal_machine.dm"
 #include "modular_zubbers\code\modules\fluff\flora\ash_flora.dm"
 #include "modular_zubbers\code\modules\food_and_drinks\machinery\stove.dm"
 #include "modular_zubbers\code\modules\food_and_drinks\recipes\drinks\drinks_alcoholic.dm"