Add support for paginated return types in Spring code generation

[Narbe66]

Added a new configOption to set return types of paginated operations. fixes #14062

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[Copilot]

Pull request overview

This PR adds support for configuring paginated return types in Spring code generation through a new paginatedReturnType configuration option. When operations use the x-spring-paginated vendor extension, developers can now choose whether collection responses should use List, Page, or Slice from Spring Data Domain.

Key Changes

• Introduced PaginatedReturnType enum with three options: LIST (default), PAGE, and SLICE
• Added logic to transform List container types to Page or Slice when x-spring-paginated is present
• Included CLI option configuration and documentation for the new feature

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SpringCodegen.java	Adds PaginatedReturnType enum, configuration option setup, and logic to transform return container types for paginated operations. Also includes several code style improvements (isEmpty, Collections.singletonList, etc.)
modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java	Adds two test cases validating PAGE and SLICE return types for paginated operations
docs/generators/spring.md	Documents the new paginatedReturnType configuration option and updates x-spring-paginated vendor extension description

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[Narbe66]

I'm not able to do the WSL part. Can some please do it for me.

[wing328]

I'm not able to do the WSL part. Can some please do it for me.

ok. we will do it later. don't worry. thanks for the PR