Surrogate & grapheme
merged
Combining marks/ZWJ wrongly treated as punctuation in emphasis (wenmode)
Fix emphasis flanking for Unicode marks and format characters
wenmode · lepture/wenmode
Symptom
wenmode's is_punctuation function treats Unicode combining marks (Mn category) and format characters (Cf/ZWJ) as punctuation per the CommonMark spec, incorrectly suppressing valid emphasis around CJK text with diacritics or ZWJ sequences.
Minimal repro
Markdown text using emphasis (* or _) adjacent to a combining mark or ZWJ character; emphasis fails to render because combining marks are classified as punctuation.
Fix
Exclude Unicode General Categories Mn, Mc, Cf from the punctuation classification; add ASCII fast-path to avoid performance regression.