Chapters, DVD subtitle palette, MKV track flags, progress total_bytes

Chapters:
- MPLS PlayList marks parsed (mark_type 1 = chapter)
- Chapter struct on DiscTitle (time_secs, name)
- MKV Chapters element with EditionEntry/ChapterAtom per mark
- 3 MPLS mark tests + 2 MKV chapter tests

DVD subtitle palette:
- IFO palette extraction (PGC offset 0xA4, 16 × YCbCr colors)
- YCbCr→RGB conversion for VobSub .idx format
- DvdSubParser codec_private returns formatted palette
- codec_data field on SubtitleStream flows through pipeline
- 5 palette tests (YCbCr conversion, formatting, overflow)

MKV track flags:
- FlagDefault: primary video/audio = 1, secondary = 0
- FlagForced: forced subtitles = 1
- Language: set from stream language code
- Already implemented, verified with 4 new tests

Progress total_bytes:
- IOStream trait: total_bytes() -> Option<u64>
- DiscStream, IsoStream: from disc_title.size_bytes
- M2tsStream, MkvStream: from file metadata on open
- NetworkStream, StdioStream, NullStream: None

316 tests total, all passing.

src/disc/bluray.rs

@@ -128,6 +128,7 @@ impl Disc {
                                 codec,
                                 language: s.language.clone(),
                                 forced: false,
+                                codec_data: None,
                             }))
                         } else {
                             Some(Stream::Audio(AudioStream {
@@ -146,6 +147,7 @@ impl Disc {
                         codec,
                         language: s.language.clone(),
                         forced: false,
+                        codec_data: None,
                     })),
                     // Stream type 4 = IG, unknown types -- skip
                     _ => None,
@@ -153,6 +155,22 @@ impl Disc {
             })
             .collect();
 
+        // Convert marks to chapters (filter mark_type == 1 = chapter entry)
+        let first_in_time = parsed.play_items.first().map(|pi| pi.in_time).unwrap_or(0);
+        let chapters: Vec<Chapter> = parsed
+            .marks
+            .iter()
+            .filter(|m| m.mark_type == 1)
+            .enumerate()
+            .map(|(i, m)| {
+                let time_secs = (m.timestamp as f64 - first_in_time as f64) / 45000.0;
+                Chapter {
+                    time_secs: if time_secs < 0.0 { 0.0 } else { time_secs },
+                    name: format!("Chapter {}", i + 1),
+                }
+            })
+            .collect();
+
         let playlist_num = filename.trim_end_matches(".mpls").trim_end_matches(".MPLS");
         let playlist_id = playlist_num.parse::<u16>().unwrap_or(0);
 
@@ -163,6 +181,7 @@ impl Disc {
             size_bytes: total_size,
             clips,
             streams,
+            chapters,
             extents,
             content_format: ContentFormat::BdTs,
         })

src/disc/dvd.rs

@@ -97,8 +97,31 @@ impl Disc {
                     .map(|e| e.sector_count as u64 * 2048)
                     .sum();
 
+                // Build pre-formatted palette codec_data for VobSub subtitle streams
+                let codec_data = dvd_title
+                    .palette
+                    .as_ref()
+                    .map(|pal| crate::mux::codec::dvdsub::format_palette(pal));
+
+                // Map DvdSubtitleAttr to Stream::Subtitle
+                let subtitle_streams: Vec<Stream> = ts
+                    .subtitle_streams
+                    .iter()
+                    .enumerate()
+                    .map(|(i, s)| {
+                        Stream::Subtitle(SubtitleStream {
+                            pid: 0x20 + i as u16, // DVD sub-stream IDs 0x20-0x3F
+                            codec: Codec::DvdSub,
+                            language: s.language.clone(),
+                            forced: false,
+                            codec_data: codec_data.clone(),
+                        })
+                    })
+                    .collect();
+
                 let mut streams = vec![video_stream.clone()];
                 streams.extend(audio_streams.iter().cloned());
+                streams.extend(subtitle_streams);
 
                 titles.push(DiscTitle {
                     playlist: format!("VTS_{:02}_{}.VOB", ts.vts_number, title_number),
@@ -107,6 +130,7 @@ impl Disc {
                     size_bytes,
                     clips: Vec::new(),
                     streams,
+                    chapters: Vec::new(),
                     extents,
                     content_format: ContentFormat::MpegPs,
                 });

src/disc/mod.rs

@@ -110,6 +110,8 @@ pub struct DiscTitle {
     pub clips: Vec<Clip>,
     /// All streams (video, audio, subtitle, etc.)
     pub streams: Vec<Stream>,
+    /// Chapter points
+    pub chapters: Vec<Chapter>,
     /// Sector extents for ripping (clip LBA ranges)
     pub extents: Vec<Extent>,
     /// Content format for this title
@@ -190,6 +192,8 @@ pub struct SubtitleStream {
     pub language: String,
     /// Whether this is a forced subtitle
     pub forced: bool,
+    /// Pre-formatted codec private data (e.g. VobSub .idx palette header)
+    pub codec_data: Option<Vec<u8>>,
 }
 
 /// Video/audio codec.
@@ -231,6 +235,15 @@ pub enum ColorSpace {
     Unknown,
 }
 
+/// A chapter point within a title.
+#[derive(Debug, Clone)]
+pub struct Chapter {
+    /// Chapter start time in seconds
+    pub time_secs: f64,
+    /// Chapter name (e.g. "Chapter 1", "Chapter 2")
+    pub name: String,
+}
+
 /// A contiguous range of sectors on disc.
 #[derive(Debug, Clone, Copy)]
 pub struct Extent {
@@ -310,6 +323,7 @@ impl DiscTitle {
             size_bytes: 0,
             clips: Vec::new(),
             streams: Vec::new(),
+            chapters: Vec::new(),
             extents: Vec::new(),
             content_format: ContentFormat::BdTs,
         }
@@ -1073,6 +1087,7 @@ mod tests {
                 secondary: false,
                 label: String::new(),
             })],
+            chapters: Vec::new(),
             extents: Vec::new(),
             content_format: ContentFormat::BdTs,
         }