Add NAPI bindings for next-code-frame
Expose the Rust code-frame implementation to Node.js via NAPI:
- Create code_frame.rs module with codeFrameColumns function
- Use From trait for clean conversions instead of manual copying
- Add Default derive to CodeFrameOptionsJs
- Document default values in doc comments (lines_above: 2, lines_below: 3)
- Add next-code-frame dependency to napi crate
This allows Next.js to use the faster, more scalable Rust implementation
instead of Babel's code-frame for error reporting.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
