feat: add ocamlformat-mlx formatter support for .mlx files

[davesnx]

Issue for this PR

Closes #14910

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Adds the ocamlformat-mlx for the mlx extension, all the info in https://github.com/ocaml-mlx/mlx

How did you verify your code works?

It follows the same structure as other formatters, I assume it works.

Screenshots / recordings

• nil

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

If you do not follow this template your PR will be automatically rejected.

[github-actions]

Hey! Your PR title Add ocamlformat-mlx formatter support for .mlx files doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

See CONTRIBUTING.md for details.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍