Effectivly gives xenochimera the weaving trait (#6981)

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## About The Pull Request

Gives Xenochimeras everything the weaving trait would give a custom
species. Given spider silk is protein fibers, it would also fit right
in, while allowing to explain the organ as a sort of fat reserve,
leaving it up to the player whether their chimera did adopt such an
ability.

## Why It's Good For The Game

Gives Xenochimeras another tool to be the spooky ambush predators in the
dark tunnels. It follows the comment that they get all the special
verbs, as they can't pick them. The only counter point may be that they
won't be affected by weaversilk traps due to having the organ, even if
in character, they never have adapted such an ability.

## Changelog

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🆑
add: Gave Xenochimeras the weaving abilities.
/🆑

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Co-authored-by: MarsMond <no@email>

code/modules/organs/internal/species/xenochimera.dm

@@ -38,3 +38,6 @@
 /obj/item/organ/internal/intestine/xenochimera
 	name = "harvesting fronds"
 	icon_state = "xenoch_intestine"
+
+/obj/item/organ/internal/weaver/weak/xenochimera
+	name = "protein reservoir"