Mux decrypt/verify redesign, HD DVD first-class, MVC 3D

decrypt:
- decrypt_sectors is now a pure decrypt (apply key, leave plaintext, report
  unverified bytes); TS-structure is a separate primitive (is_clean_ts/ps) used
  only for key selection and read-verify. The mux passes decrypted bytes through
  (the demuxer drops non-conforming packets), ending the NULL-TS conceal loop and
  the per-unit key-server refetch storm. Key-proof floor replaces the 75%
  supermajority.

recovery:
- Removed the post-read decrypt-verify gate (verify.rs) that mis-aligned the
  disc-absolute unit grid against clip-anchored AACS units and false-failed good
  clips (e.g. Dunkirk's orphan-CPS clip). Bad sectors are marked by physical read
  result; decryptability is proven at scan + mux time.

HD DVD (first-class AACS):
- Role-based candidate-list file sourcing so an HD DVD's /ANY!/ files
  (MKBROM.AACS, VTKF000.AACS, CONTENT_CERT.AACS) are found with no disc-type
  branch. parse_vtkf parses VTKF000.AACS into the same UnitKeyFile as a BD
  Unit_Key_RO.inf, so the shared VUK unwrap applies unchanged. set_unit_base
  clip-anchoring. Two decrypt-axis assumptions remain UNVERIFIED-HDDVD-DECRYPT
  (no encrypted disc to test).

mux:
- MVC (Blu-ray 3D) track signals unified into one MVCDecoderConfigurationRecord;
  release-safe track_vint (3-byte VINT) and pid_index (i32) guards.

hardening:
- Container-aware is_clean / encryption detection; bytes_bad_in_title fail-safe
  on a corrupt mapfile; CSS crack gated on DiscFormat::Dvd (HD DVD excluded);
  non-vacuous CSS tests; patch NOT_READY/HARDWARE/ILLEGAL_REQUEST/ABORTED
  sense-path tests.

src/disc/sweep.rs

@@ -66,14 +66,6 @@ pub(super) enum WorkItem {
     /// tell them apart without parsing a flag.
     GapFill { pos: u64, len: u64 },
 
-    /// Post-read verify downgrade. The producer's `UnitVerifier` found that the
-    /// just-`Finished` clip unit at `[pos, pos+len)` is confidently undecryptable
-    /// (a silent bad read). The consumer re-records the range as `NonTrimmed` so
-    /// the patch pass re-reads it — the ISO bytes (ciphertext) already written by
-    /// the preceding `Good` are left in place for the patch to overwrite. FIFO
-    /// pipe ordering guarantees this arrives AFTER the `Good` that wrote them.
-    MarkBad { pos: u64, len: u64 },
-
     /// Producer wants the latest mapfile stats for the progress
     /// callback. Consumer responds on `prog_tx` with a fresh
     /// [`ProgressSnapshot`]. Best-effort: if the producer hasn't
@@ -182,12 +174,6 @@ impl Sink<WorkItem> for SweepSink {
                 }
                 self.map.record(pos, len, SectorStatus::NonTrimmed)?;
             }
-            WorkItem::MarkBad { pos, len } => {
-                // Verify downgrade: the ISO bytes are already written by the
-                // preceding Good; only the mapfile status changes so patch
-                // re-reads this range. No file write.
-                self.map.record(pos, len, SectorStatus::NonTrimmed)?;
-            }
             WorkItem::StatsRequest => {
                 let stats = self.map.stats();
                 // DAMAGE only — NOT NonTried. NonTried is the unread remainder