feat: add pre-commit hook for oxfmt

[kennethnym]

Description

Add a pre-commit hook that runs oxfmt on staged files via husky + lint-staged, so formatting is enforced automatically on every commit.

How to test

1. bun install
2. Stage a .ts file with bad formatting
3. git commit — lint-staged should auto-format the file before committing

[ona-patrol]

Reviewed the changes. Implementation looks solid — standard husky + lint-staged setup, bunx usage is consistent with the bun-based project, and the lint-staged glob covers the file types oxfmt supports. No significant concerns.

[ona-patrol]

Reviewed the changes. Implementation looks solid — husky + lint-staged is the standard approach for pre-commit formatting, the glob pattern covers the project's main file types, and the existing oxfmt configuration (including ignore patterns in .oxfmtrc.json) is respected. No significant concerns.