Per-playlist stream_number counters were resetting between MPLS
files, so a disc with 2 MPLS files each listing the same 8 audio
streams produced labels with stream_number 1..8 then 1..8 again
(dedup kept whichever PID was different, leaving the numbering
visibly broken — multiple "audio1: eng" rows).
Move the counters outside the per-file loop and increment only
when an entry survives dedup. Surviving entries now get dense
1..N numbering across the whole disc per stream_type.
Verified on corpus disc-02 (HDMV-only): was `audio1, audio1, audio1`
for the 3 distinct audio codecs (TrueHD/AC-3/DTS-HD MA), now
`audio1, audio2, audio3`. Same fix applies to disc-01 (12 audio
streams across multiple MPLS) and disc-09 (14 audio streams).
Three new modules in the labels platform, all layered so framework-
specific parsers (paramount, criterion, pixelogic, ctrm, dbp, deluxe)
always take precedence over the universal layer.
**mpls_universal.rs** (~600 LOC, 9 tests): consumes the already-parsed
`crate::mpls::Playlist::streams` and emits StreamLabel entries with
language + codec_hint per stream. Returns `Confidence::Low` (new
variant) so framework parsers' Medium/High always win the registry's
max-by-confidence tiebreaker; MPLS only gets picked when no framework
matched. Closes the "no BD-J disc" case (HDMV-only navigation) that
previously produced zero labels — language and base codec are
spec-mandated in MPLS STN tables on every Blu-ray ever made.
**bdmt.rs** (~350 LOC, 10 tests): reads `/BDMV/META/DL/bdmt_<lang>.xml`
files into a new `DiscMetadata` struct (localized title names per
ISO 639-2 code, descriptions, optional box-set position). Runs
independently of the parser registry — disc-level metadata, not
per-stream, so the registry's confidence selection doesn't apply.
Surfaced on a new `LabelAnalysis::disc_metadata` field.
**png_filenames.rs** (noop stub): pattern documentation + dead-code
detect/parse for future reactivation. Deferred because MPLS already
delivers per-stream lang/codec/type on every disc; PNG filename
language tokens only add studio variant disambiguation (FRC vs FRP,
LAS vs CSP) — niche enough to not justify the implementation cost
right now.
Wiring changes in `mod.rs`:
- New `Confidence::Low` variant (PartialOrd places it below Medium/High)
- New `ParseResult::low()` constructor
- `mpls_universal` appended last to `PARSERS` registry
- `LabelAnalysis::disc_metadata: Option<DiscMetadata>` field
- `analyze()` runs `bdmt::parse` independently and surfaces result
- `pub use bdmt::DiscMetadata` re-export so the labels-analyze tool
in freemkv-tools can construct the JSON payload
Total: 151 of 151 labels tests passing (was 132 — added 19 new).