~jaro/balkon

ref: e5196add6c88a4034109c516d6c338becfea7c6c 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.