The Phase 4 walker + rescan logic classified seasons by parser
output (does the filename carry Exx?), but PACK vs EPISODIC is a
structural distinction:
* PACK = season folder with N flat SxxEyy videos directly inside
* EPISODIC = season folder with N subfolders, each holding one video
Changes:
* walker.py: descends two levels under show_root and classifies
each season folder by FS structure. SeasonFolder now carries
mode: ReleaseMode | None. Mixed layouts (flat + subfolders) and
EPISODIC subfolders with >1 video log a warning and report
mode=None.
* rescan.py: trusts walker.mode; drops the bogus 'single un-
numbered video → PACK with empty episodes' branch. A season
with no parseable episodes is now skipped with a warning.
* Tests rewritten against the real model: PACK with flat numbered
files, EPISODIC with one-video-per-subfolder, malformed mixed
layout skipped, single-un-numbered-file skipped.
Suite: 1237 → 1245 passing.
francwa
97dc799a26