Pixelogic discs that authored a SEG_MainFeature menu/preview segment
containing a stray commentary token made the parser anchor on that
segment instead of the real FPL_MainFeature playlist. Combined with
'Audio Stream N' placeholder tokens not advancing the audio counter, a
lone eng_ACOM_ commentary at STN slot 4 collapsed onto slot 1 — tagging
the main feature track as Commentary (seen on Wicked: For Good).
Fix:
- Anchor the feature section on the FPL_ playlist when present; only
fall back to SEG_MainFeature on discs with no FPL_ section.
- Count 'Audio Stream N' placeholders so editorial audio tokens get
their true STN ordinal. Subtitle (PG Stream N) numbering is left
unchanged — counting it regressed several corpus discs.
Extract the section/numbering loop into assign_labels with unit tests.
Verified: 11/11 labels-corpus discs still PASS; Wicked commentary now
lands on the AC-3 2.0 stereo track instead of the main TrueHD.
MattJackson
c0478e1273