Disc::titles previously sorted purely by duration_secs descending,
which puts a play-all virtual playlist at index 0 on UHDs that ship
one. Such playlists reference the same source clips multiple times
for seamless alternate-angle / alternate-ending playback and report
inflated duration AND inflated size_bytes that exceeds the disc's
physical capacity.
Concrete observed case (The Amateur 2025 4K UHD, 58.5 GB BD-100):
Title 1 — 00020.mpls — 4h13m — 92.4 GB — 253 clips ← impossible
Title 2 — 00800.mpls — 2h02m — 57.2 GB — 1 clip ← the movie
92.4 GB > 58.5 GB capacity is proof of clip double-counting. With
the duration-only sort, freemkv -t 1 / disc.titles.first() / autorip's
main-feature picker all selected the 4-hour composite instead of the
2-hour movie.
New canonical_title_order:
1. Real titles (size_bytes <= capacity_bytes) before virtual
composites — capacity gate is hard physical truth.
2. Among real titles, fewer clips first (1-clip wins as the
canonical main feature; multi-clip is either chapter-stitched
or composite).
3. Tiebreak on longer duration first.
Behaviour:
- Non-branching discs: unchanged. The longest 1-clip title is
already the movie.
- Branching UHDs: virtual composite drops to the back, the real
movie surfaces at index 0.
Comparator exposed as Disc::canonical_title_order for downstream
consumers that need the same logic on custom title sets.
Three regression tests (disc::tests::canonical_order_*):
- pushes_oversize_play_all_behind_real_main (The Amateur)
- preserves_natural_ranking_on_normal_disc
- fewer_clips_wins_tiebreak
matthew
518c5293c8