chore: refactor date library usage to use CodegenConstants.DATE_LIBRARY

[ChihweiLHBird]

PR checklist

• Read the contribution guidelines.
• Ran the shell script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh and ./bin/security/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates). Windows batch files can be found in .\bin\windows\.
• Filed the PR against the correct branch: 3.0.0 branch for changes related to OpenAPI spec 3.0. Default: master.

Description of the PR

Since this may be considered as a breaking change, I would like to leave the decision making to the team.

• Move DATE_LIBRARY to CodegenConstants as it is shared across
  the Java and Kotlin language families
• Add @Deprecated aliases in AbstractJavaCodegen and
  KotlinClientCodegen for backward compatibility

[Copilot]

Pull request overview

Refactors Java/Kotlin codegen option handling so dateLibrary is sourced from the shared CodegenConstants.DATE_LIBRARY, reducing duplication across language families and aligning option keys.

Changes:

• Introduce CodegenConstants.DATE_LIBRARY and update generators/tests to use it.
• Add @Deprecated aliases for DATE_LIBRARY in AbstractJavaCodegen and KotlinClientCodegen.
• Remove AbstractJavaCodegen’s locally-declared WITH_XML constant and switch internal usage to CodegenConstants.WITH_XML.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
modules/swagger-codegen/src/test/java/io/swagger/codegen/options/KotlinClientCodegenOptionsProvider.java	Update test options to use CodegenConstants.DATE_LIBRARY.
modules/swagger-codegen/src/test/java/io/swagger/codegen/options/JaxRSServerOptionsProvider.java	Update test options to use CodegenConstants.DATE_LIBRARY / CodegenConstants.WITH_XML.
modules/swagger-codegen/src/test/java/io/swagger/codegen/options/JavaOptionsProvider.java	Update test options to use CodegenConstants.DATE_LIBRARY / CodegenConstants.WITH_XML.
modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/SpringCodegen.java	Switch dateLibrary defaulting check to CodegenConstants.DATE_LIBRARY.
modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/KotlinClientCodegen.java	Deprecate local DATE_LIBRARY constant and use CodegenConstants.DATE_LIBRARY throughout.
modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java	Deprecate local DATE_LIBRARY, remove local WITH_XML, and use CodegenConstants keys internally.
modules/swagger-codegen/src/main/java/io/swagger/codegen/CodegenConstants.java	Add shared DATE_LIBRARY constant.

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Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

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Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java:65

• WITH_XML is still declared locally in AbstractJavaCodegen even though CodegenConstants.WITH_XML already exists. This keeps the shadowing/duplication the PR description says was removed, and makes it easy for the two definitions to drift. Consider removing the local WITH_XML constant and switching its usages to CodegenConstants.WITH_XML (or, if you need backward compatibility for external references, keep a deprecated alias similar to DATE_LIBRARY).

    public static final String DEFAULT_LIBRARY = "<default>";
    public static final String JAVA8_MODE = "java8";
    public static final String JAVA11_MODE = "java11";
    public static final String SUPPORT_ASYNC = "supportAsync";
    public static final String WITH_XML = "withXml";

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Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated no new comments.

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