#24180 [Java] Add USE_ENUM_CASE_INSENSITIVE for java client generator

Add USE_ENUM_CASE_INSENSITIVE for java client generator, also add test

PR checklist

• Read the contribution guidelines.
• 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
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request.

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Summary by cubic

Adds case-insensitive enum matching to the Java MicroProfile client generator. When useEnumCaseInsensitive is enabled, generated enums accept values regardless of case in fromValue and during jackson deserialization.

• New Features

  • Added additionalProperties.useEnumCaseInsensitive for the java generator (microprofile library); when enabled, uses equalsIgnoreCase in enumClass.mustache (including the Jackson enum deserializer) and enumOuterClass.mustache.
  • Added bin/configs/java-microprofile-rest-client-3.0-jackson-ignore-case.yaml and a generated sample under samples/client/petstore/java/microprofile-rest-client-3.0-jackson-ignore-case to validate equalsIgnoreCase behavior with MicroProfile Rest Client 3.0 and jackson.

• Migration

  • Enable with --additional-properties useEnumCaseInsensitive=true (or useEnumCaseInsensitive: true in your config).