New module: src/rendering/framebuffer.lisp (tangled from org/framebuffer.org)
- framebuffer-backend class: implements backend protocol by writing to
2D cell array instead of emitting escape sequences
- cell struct: per-cell state (char, fg, bg, bold, italic, underline, link-url)
- make-framebuffer / framebuffer-width / framebuffer-height
- draw-text, draw-rect, draw-border, draw-link, draw-ellipsis methods
- diff-framebuffers: compares two framebuffers, returns changed cells
- flush-framebuffer: diff + output changes to real backend
- with-scissor macro: clip drawing operations to rectangle
- cursor-move: added default no-op method for all backends
- 20 new tests, all passing (372 total)
Version bumped from 0.11.0 to 0.13.0.
License field set to GPL-3.0 in ASDF.
- Box class with border-style, title, fg/bg slots
- render-box dispatches through backend protocol
- draw-border for borders, draw-rect for background
- draw-text for title below top border
- 7 tests: defaults, border, background, title, no-border,
zero-size, minimum-size
- 13 assertions, 100% GREEN
- ASDF updated with src/components module
- modern-backend now accepts :output-stream initarg
