~jaro/balkon

ref: e29432083612d3bba827cd0e9a3594be8c5b95ed balkon/src/Data/Text/ParagraphLayout/Internal/ProtoRun.hs -rw-r--r-- 461 bytes
Integrate BiDi levels with spanToRuns algorithm.

Span/box boundaries no longer reset directionality.

BREAKING: Text with no strongly directional characters would
previously be treated as having no direction. It will now be
treated as having the direction defined in TextOptions.
This affects calculated positions.
Prepare for extending ProtoRun.