Fix jaxrs-spec CI failures

[wing328]

a follow up PR to #23509

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---

Summary by cubic

Switch JAX-RS sample configs to the OAS3 Petstore and regenerate samples to align with current generator output, resolving CI snapshot mismatches for jaxrs-spec.
This updates inputs and samples only; no generator logic changes.

• Bug Fixes
  • Pointed bin/configs/jaxrs-spec-interface*.yaml and jaxrs-spec-quarkus-microprofile-openapi-annotations.yaml to modules/openapi-generator/src/test/resources/3_0/petstore.yaml (was OAS2).
  • Regenerated samples/server/petstore/jaxrs-spec-interface* using OAS3 Petstore: removed legacy “fake” endpoints/models and refreshed openapi.yaml.
  • Fixed generated API signatures and annotations:
    • Renamed path params order_id → orderId.
    • Renamed request params body → pet/user; added @Produces to addPet; updated auth annotations.
    • Dropped RestApplication/RestResourceRoot scaffolding.
  • Updated model docs (e.g., Category, Pet, Tag, User, Order, ModelApiResponse) and removed unused models to match OAS3 schema.
  • CI: sample outputs now match expectations and JAX-RS jobs should pass.

^{Written for commit f448007. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 169 files

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