Module pairing 

Pair deleted/added line runs inside a hunk and attach intra-line emphasis. Lines pair positionally within a run, gated by similarity, mirroring delta’s homologous-line model.

Functions

enrich_file

Attach intra-line emphasis to one file’s hunks. Pairing is a render-time concern (only the TUI reads .emphasis), so callers enrich the file they are about to display rather than enriching whole models up front.