[OCaml][Fix] Unreferenced enum + Direct recursive types

[sir4ur0n]

• Add support for directly recursive types (e.g., A -> A)
  • Mutually recursive types are not supported because this is MUCH more complex to implement in OCaml and I don't have the time to do the huge refactor needed for them
• Fix a bug where empty string enums broke generation
• Fix a bug where enums inside anyOf/oneOf/allOf were not correctly detected

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• 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
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
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  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
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@cgensoul @wing328

CI fails for seemingly unrelated reasons but I can't manually restart it.

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Summary by cubic

Fixes OCaml generator crashes with enums inside anyOf/allOf/oneOf and adds first-class support for direct self-recursive models across fields, arrays, and maps. Adds tests and samples, updates CI to OCaml 5.3, and improves generated README titles.

• Bug Fixes

  • Traverse composed schemas to collect enums (including branch-level and nested $ref) and prefix their types with Enums.
  • Use order‑independent enum hashing with Set, fixing “unreferenced enum” and supporting empty‑string enum values.

• New Features

  • Normalize self-references to t for direct recursion in properties, arrays, and maps; support required recursive fields and multiple recursive properties.
  • Add 3.0 test specs and samples for composed-schema enums and recursion; remove “(beta)” from OCaml generator help and title READMEs as “OCaml API client for ”.

^{Written for commit df59629. Summary will update on new commits.}

[sir4ur0n]

@cgensoul @wing328 this is ready for review 🙏

[cubic-dev-ai]

3 issues found across 49 files

Prompt for AI agents (all 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="samples/client/petstore/ocaml-recursion-test/README.md">

<violation number="1" location="samples/client/petstore/ocaml-recursion-test/README.md:1">
P2: Malformed Markdown header - title text should be on the same line as the `#` marker</violation>
</file>

<file name="samples/client/petstore/ocaml-recursion-test/src/models/required_recursion.ml">

<violation number="1" location="samples/client/petstore/ocaml-recursion-test/src/models/required_recursion.ml:18">
P1: Syntax error in generated OCaml record: `[@key]` attributes are misplaced after field separators (`;`). Attributes must be placed after the field type and BEFORE the semicolon, e.g., `value: string [@key "value"];`. The current placement will cause compilation failure and break JSON serialization.</violation>
</file>

<file name="samples/client/petstore/ocaml-enum-in-composed-schema/src/models/test_model.ml">

<violation number="1" location="samples/client/petstore/ocaml-enum-in-composed-schema/src/models/test_model.ml:17">
P0: Incorrect placement of `[@key]` attributes breaks JSON serialization mappings</violation>
</file>

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