~jaro/balkon

ref: 5e3e1e93561ccc12946b476272cb0bd211dc4a22 balkon/src/Data/Text/ParagraphLayout/Internal/Rich.hs -rw-r--r-- 3.1 KiB
Link ResolvedSpan to boxes.
Separate WithSpan for sharing with other modules.
Add basic support for Rich layout.