v0.8.0: Markdown + Code + Diff rendering module
Add cl-tui.markdown package with:
- Markdown parser: headings, paragraphs, bold, italic, inline-code, links,
code blocks, blockquotes, lists, thematic breaks
- Syntax highlighting: Lisp, Python, JavaScript, Bash with keyword,
builtin, comment, number, function coloring
- Diff renderer: colorized unified diff (+/-/@ lines)
- Terminal renderer: ANSI escape sequences via backend-style functions
- 67 tests, 100% passing
- All parser helpers use values returns (not cons) for multiple-value-bind
ASDF: v0.7.0 -> v0.8.0, new markdown module + test suite
9648c72b85