Implement Phase 4: Syntax highlighting architecture with OXC
Changes:
- Replace SWC with OXC parser for better API accessibility
- Implement offset/marker pair approach for style tracking
- Extract highlights by visiting OXC AST (strings, numbers, regex, templates)
- Split style markers across line boundaries (no spans cross newlines)
- Implement apply_line_highlights() for late ANSI code insertion
Architecture:
- `extract_highlights()` - Parse entire file once with OXC, extract all tokens
- `StyleMarker` - Records start/end of styled regions by byte offset
- `LineHighlight` - Per-line highlighting info with line-relative offsets
- `split_markers_by_line()` - Ensures markers never cross line boundaries
- `apply_line_highlights()` - Applies ANSI codes during rendering
Benefits:
- OXC parser is fast and has accessible public API
- Line-oriented rendering never needs to handle newlines in styles
- Late insertion prevents column offset issues
- Supports multiline tokens (template literals, strings) properly
Dependencies added:
- oxc_parser, oxc_ast, oxc_span, oxc_allocator (0.42.0)
- Removed swc_core dependency
Next: Integrate into frame rendering and add ANSI stripping for tests
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
