Add USE_ENUM_CASE_INSENSITIVE for jaxrs-spec generator, mustache files already have that.

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• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

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Summary by cubic

Adds a useEnumCaseInsensitive option to the jaxrs-spec generator for case-insensitive String enum matching. Includes a new Petstore sample with tests and updates docs for jaxrs-spec and jaxrs-cxf-cdi.

• New Features
  • New CLI/config option useEnumCaseInsensitive (default: false) in org.openapitools.codegen.languages.JavaJAXRSSpecServerCodegen; exposed to templates via additionalProperties.
  • Added bin/configs/jaxrs-spec-enum.yaml and generated samples/server/petstore/jaxrs-spec-enum (tests validate case-insensitive .fromValue() for string enums). Updated docs for jaxrs-spec and jaxrs-cxf-cdi.

^{Written for commit 7d16a45. Summary will update on new commits.}