[SPRING;KOTLIN-SPRING] Fix: enhance pageable parameter detection with OpenAPI reference resolution

[Picazsoo]

fixes #24719

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Summary by cubic

Fixes pageable auto-detection in Spring and Kotlin-Spring by resolving OpenAPI parameter refs. Previously, operations using #/components/parameters for page, size, or sort were not detected; now they inject Pageable and generate validations from referenced schemas.

• SpringPageableScanUtils resolves refs via ModelUtils.getReferencedParameter; overloads willBePageable and applyAutoXSpringPaginatedIfNeeded to accept OpenAPI; scans for defaults, constraints, and sort enums resolve refs.
• SpringCodegen and KotlinSpringServerCodegen now pass openAPI to applyAutoXSpringPaginatedIfNeeded.
• Honors x-spring-paginated: false and AUTO_X_SPRING_PAGINATED; unresolved refs do not trigger detection.
• Adds OAS 3.1 tests and a fixture validating ref-driven Pageable injection, defaults (@PageableDefault), constraints (@ValidPageable), and sort validation (@ValidSort), plus a test ensuring unresolved refs are ignored.

^{Written for commit eb4eda8. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 7 files

_{Re-trigger cubic}