[Kotlin][Spring] fix option useSpringBuiltInValidation not implemented

[wing328]

based on #23951 with updated doc, bug fix.

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---

Summary by cubic

Fixes the kotlin-spring generator so useSpringBuiltInValidation disables class-level @Validated on generated controllers and interfaces when useBeanValidation is on. Default behavior is unchanged.

• Bug Fixes
  • Wired the option in KotlinSpringServerCodegen (flag, CLI switch, processOpts/writePropertyBack).
  • Updated api.mustache and apiInterface.mustache to skip the import and annotation when enabled.
  • Added tests for interface/controller and default/true/false cases.
  • Documented the option in docs/generators/kotlin-spring.md.

^{Written for commit bb4112b. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 5 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinSpringServerCodegen.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinSpringServerCodegen.java:533">
P1: Missing `writePropertyBack(USE_SPRING_BUILT_IN_VALIDATION, useSpringBuiltInValidation)`. Without it, the flag value never reaches the Mustache template context. When the user explicitly passes `useSpringBuiltInValidation=false`, the String `"false"` left in `additionalProperties` is truthy in Mustache, so `{{^useSpringBuiltInValidation}}` incorrectly fails to render, causing `@Validated` to be skipped despite the flag being false.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>