feat: add oxfmt as a formatter option

[stevan-borus]

Description

Add support for oxfmt (the Oxc formatter) as a third formatter option alongside biome and prettier.

oxfmt >=0.36.0 supports stdin formatting via --stdin-filepath, which follows the same pipe-in/pipe-out pattern already used by biome and prettier. It can format both TypeScript and HTML/SVG files.

Usage

iconsSpritesheet({
  inputDir: './icons',
  outputDir: './output',
  formatter: 'oxfmt',
})

Changes

• Added "oxfmt" to the Formatter type union
• Added oxfmt CLI args (--stdin-filepath file.ts / --stdin-filepath file.html) in lintFileContent
• Refactored formatter options selection from ternary to a Record<Formatter, string[]> map for clarity
• Updated JSDoc comments
• Added oxfmt as a devDependency for testing
• Added tests verifying stdin formatting works for both TypeScript and HTML/SVG

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Algorithm update - updates algorithm documentation/questions/answers etc.
• Other (please describe):

How Has This Been Tested?

• Integration tests
• Unit tests
• Manual tests
• No tests required

Unit tests:

• should format TypeScript via stdin — pipes TS content through oxfmt and verifies semicolons, parenthesized typeof, and content preservation
• should format HTML/SVG via stdin — pipes SVG content through oxfmt and verifies multi-line formatted output

Manual test steps:

1. Install oxfmt >=0.36.0 in a project
2. Configure iconsSpritesheet({ ..., formatter: 'oxfmt' }) in vite.config.ts
3. Run vite dev
4. Verify generated types file and SVG spritesheet are formatted by oxfmt

Tested with oxfmt 0.36.0, Vite 7.3.1, and React Router 7.13.1.

Reviewer checklist

• Check if the UI is working as expected and is satisfactory
• Check if the code is well documented
• Check if the behavior is what is expected
• Check if the code is well tested
• Check if the code is readable and well formatted
• Additional checks (document below if any)

Screenshots (if appropriate):

N/A — build-time plugin, no UI changes.

Questions (if appropriate):

N/A

[sairus2k]

You could try my fork, I added oxfmt support already

https://github.com/MyEasyFarm/vite-plugin-icons-spritesheet