DRAFT: Pr1 jaxrs useoneofinterfaces

[Ignacio-Vidal]

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Summary by cubic

Fixes discriminator type resolution for oneOf/anyOf interfaces and adds useOneOfInterfaces support to jaxrs-spec. Interfaces now use the correct enum type instead of String; feature is opt-in and default output is unchanged.

• Bug Fixes

  • Resolve discriminator property type from child schemas (oneOf/anyOf), following allOf into shared bases to get the enum ref instead of falling back to String.
  • Prevent infinite recursion by guarding against cyclic allOf compositions.
  • Update DefaultCodegen to use the new resolution with a safe "string" fallback when no typed schema is found.

• New Features

  • jaxrs-spec: generate Java interfaces for oneOf when useOneOfInterfaces=true via a new oneof_interface.mustache template.
  • Interface includes Jackson type info and declares the discriminator getter with the resolved type; concrete subtypes implement it.
  • Add sample samples/server/petstore/jaxrs-spec-oneof-interface, tests, and CI workflow entry.

^{Written for commit 280a2f6. Summary will update on new commits.}