ci(format): replace Prettier with oxfmt

[Slashgear]

Proposal — This PR is submitted for the documentation team's review. It is not meant to be merged as-is without collective validation.

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Why oxfmt?

The repo currently uses Prettier to format JSON files. Prettier is a great tool, but it has some limitations in our context:

• It is slow on large repos (every file is parsed in JS)
• Its configuration is spread across .prettierrc and .prettierignore
• It is not designed to be lightweight

oxfmt is an alternative formatter, written in Rust and distributed via npm. It is compatible with Prettier's configuration (same options: singleQuote, trailingComma, semi, etc.) but offers dramatically better performance.

Concrete result: oxfmt formats every file in the repo in a few milliseconds, whereas Prettier takes several seconds.

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What this PR changes

Before	After
prettier	oxfmt
.prettierrc + .prettierignore	.oxfmtrc.json
No CI check	format job in the GitHub Actions workflow

Modified files

• package.json — replaces prettier with oxfmt in devDependencies and the format script
• .oxfmtrc.json — new config file (equivalent to the previous .prettierrc)
• .prettierrc / .prettierignore — removed
• .github/workflows/format.yml — adds a format job that installs dependencies and checks formatting on every PR
• .github/labeler.yml — updates the .prettierrc reference to .oxfmtrc.json

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IDE integration

oxfmt ships a drop-in replacement for Prettier's CLI — it registers itself as node_modules/.bin/prettier after pnpm install. This means existing IDE integrations pick it up automatically, with no reconfiguration needed:

• VS Code: any formatter extension that relies on the local prettier binary (e.g. the official Prettier extension) will transparently use oxfmt instead
• WebStorm / IntelliJ: same — the built-in "Prettier" formatter setting points to the local binary and will use oxfmt without any change
• Neovim / other: tools like conform.nvim or null-ls that invoke node_modules/.bin/prettier will work as-is

In short: run pnpm install, and your editor formats with oxfmt automatically.

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CI

A format job is added to .github/workflows/format.yml. It runs on every PR and verifies that all files are properly formatted using oxfmt (pnpm format --check). If a file is not formatted, the PR is blocked with a clear diff.

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Open questions for the team

• Do we want to extend formatting to .md / .mdx files in addition to .json?
• Do we want to enforce the format check as a required status check on main?