[jaxrs-spec] Emit @Email bean validation for string with format: email

[Ignacio-Vidal]

Adds @Email bean-validation support to the jaxrs-spec server generator so that type: string / format: email properties and parameters are validated at runtime, matching the behaviour already provided by the Spring generator.

Background

DefaultCodegen already sets isEmail = true for format: email schemas across every Java generator, but jaxrs-spec's beanValidationCore.mustache never consumed the flag. As a result email fields/parameters were emitted as a plain String with no @Email constraint (documentation-only), unlike Spring which renders @Email.

Change

• emit @Email when isEmail is set under useBeanValidation
• No new import is required — javax/jakarta package is selected automatically (including under useJakartaEe=true).

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
  

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  Commit all changed files.
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  These must match the expectations made by your contribution.
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Summary by cubic

Adds @Email bean validation to the jaxrs-spec server generator for type: string with format: email so models and query params are validated at runtime, matching Spring. Active only when useBeanValidation is enabled.

• New Features

  • Emit @Email when isEmail is set in beanValidationCore.mustache.
  • Uses existing wildcard import {{javaxPackage}}.validation.constraints.* for javax/jakarta.
  • Applies to models and query parameters; inherited by all jaxrs-spec libraries.

• Tests

  • Expanded issue_4876_format_email.yaml with a required format: email query parameter; added tests for javax, jakarta, and disabled useBeanValidation.
  • Updated required-and-readonly-property.yaml and regenerated the jaxrs-spec-required-and-readonly-property sample with required/optional email fields to verify @Email output compiles.

^{Written for commit aecbe3d. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[Ignacio-Vidal]

@wing328 - could you review this small PR?