Add Snails (#30765)

* add snails

* scuffix

* migrate

* mo-grate

* oopsied the ftls

* Revert "oopsied the ftls"

This reverts commit 0d3c6c17f31ec904679d6a48799cea71e77c1f99.

* the curse of staging the wrong file, resolved.

* Snoth

* fix my dumbs

* reviews 1

* anti space technology

* salt hurty

* spelling

* Its a slotherhouse out here

* sequencing

* cooked snail

* volfix

* speed reversal

Resources/Prototypes/GameRules/events.yml

@@ -337,6 +337,48 @@
     - id: MobMothroach
       prob: 0.008
 
+- type: entity
+  id: SnailMigrationLowPop
+  parent: BaseStationEventShortDelay
+  components:
+  - type: StationEvent
+    startAnnouncement: station-event-vent-creatures-start-announcement
+    startAudio:
+      path: /Audio/Announcements/attention.ogg
+    weight: 6
+    duration: 50
+  - type: VentCrittersRule
+    entries:
+    - id: MobSnail
+      prob: 0.02
+    - id: MobSnailSpeed
+      prob: 0.002
+    - id: MobSnailMoth
+      prob: 0.002
+
+- type: entity
+  id: SnailMigration
+  parent: BaseStationEventShortDelay
+  components:
+  - type: StationEvent
+    startAnnouncement: station-event-vent-creatures-start-announcement
+    startAudio:
+      path: /Audio/Announcements/attention.ogg
+    earliestStart: 15
+    weight: 6
+    duration: 50
+    minimumPlayers: 30
+  - type: VentCrittersRule
+    entries:
+    - id: MobSnail
+      prob: 0.02
+    - id: MobSnailSpeed
+      prob: 0.002
+    - id: MobSnailMoth
+      prob: 0.002
+    - id: MobSnailInstantDeath
+      prob: 0.00001 #  ~ 1:2000 snails
+
 - type: entity
   id: PowerGridCheck
   parent: BaseStationEventShortDelay