Arachne Silk Production Factory (#205)

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# Description

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Arachne can use that large abdomen of theirs to produce silk. (They
couldn't take the bionic spinnerette trait and their placed webs do not
produce silk)

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# TODO

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- [x] spider butt

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# Changelog

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:cl:
- add: Added ability for Arachne to produce silk

Co-authored-by: KyuPolaris <[email protected]>
Co-authored-by: sleepyyapril <[email protected]>

Resources/Prototypes/Entities/Mobs/Species/arachne.yml

@@ -88,6 +88,11 @@
       visible: false
   - type: HumanoidAppearance
     species: Arachne
+  - type: Sericulture
+    action: ActionSericulture
+    productionLength: 2
+    entityProduced: MaterialWebSilk1
+    hungerCost: 4 # Should total to 25 total silk on full hunger
   - type: Fixtures
     fixtures: # TODO: This needs a second fixture just for mob collisions.
       fix1: