0.31.0: hardening and correctness pass across mux, codec, AACS/CSS, UDF/MPLS/CLPI, recovery, drive/SCSI, labels, and I/O

Library-wide review-and-fix pass: tightened AACS keydb/handshake/variant
handling and trailing-partial-unit policy, corrected MPLS mark offset and
added UDF allocation bounds, hardened the mux/codec framing and M2TS paths,
guarded SCSI READ CAPACITY short transfers and unified error mapping, added
overflow guards on untrusted disc input, and made prefetch shutdown
deterministic. Release profile now builds with thin LTO + single codegen unit.

src/disc/dvd.rs

@@ -34,15 +34,27 @@ impl Disc {
                 label: String::new(),
             });
 
-            // Map DvdAudioAttr to Stream::Audio
+            // Map DvdAudioAttr to Stream::Audio. The PID is derived from the
+            // stream's REAL on-wire private_stream_1 sub-stream id (assigned
+            // by per-codec ordinal in the IFO scan) via the same
+            // `dvd_audio_pid` table the demuxer's `PsPacket::dvd_pid` uses,
+            // so a mixed-codec title (AC-3 + DTS + LPCM) routes correctly
+            // instead of colliding on 0xBD00. Streams carried as a regular
+            // MPEG-audio PES (MP1/MP2, no sub-id) fall back to a distinct
+            // 0xBD00+ordinal PID — disjoint from the 0xBD80+ canonical audio
+            // space — though they are not routed via `dvd_pid` today.
             let audio_streams: Vec<Stream> = ts
                 .audio_streams
                 .iter()
                 .enumerate()
                 .map(|(i, a)| {
                     let codec = a.codec;
+                    let pid = a
+                        .sub_stream_id
+                        .and_then(crate::mux::ps::dvd_audio_pid)
+                        .unwrap_or(0xBD00 + i as u16);
                     Stream::Audio(AudioStream {
-                        pid: 0xBD00 + i as u16, // DVD private stream 1 sub-IDs
+                        pid,
                         codec,
                         channels: AudioChannels::from_count(a.channels),
                         language: a.language.clone(),
@@ -88,8 +100,13 @@ impl Disc {
                     .iter()
                     .enumerate()
                     .map(|(i, s)| {
+                        // VobSub sub-stream ids run 0x20..=0x3F; PID = sub-id
+                        // (identity), shared with the demuxer via
+                        // `dvd_subtitle_pid`.
+                        let sub_id = 0x20u8.saturating_add(i.min(0x1F) as u8);
+                        let pid = crate::mux::ps::dvd_subtitle_pid(sub_id).unwrap_or(sub_id as u16);
                         Stream::Subtitle(SubtitleStream {
-                            pid: 0x20 + i as u16, // DVD sub-stream IDs 0x20-0x3F
+                            pid,
                             codec: Codec::DvdSub,
                             language: s.language.clone(),
                             forced: false,
@@ -109,7 +126,7 @@ impl Disc {
                     .enumerate()
                     .map(|(i, &t)| Chapter {
                         time_secs: t,
-                        name: format!("Chapter {}", i + 1),
+                        name: chapter_name(i),
                     })
                     .collect();