v0.25.2: DTS-HD codec ID + PGS BlockDuration

- MkvTrack::audio emits A_DTS/MA, A_DTS/HR, A_DTS per the DTS family
  instead of mislabelling everything as A_DTS. Plex transcoder and
  strict hardware decoders reject DTS-HD MA payload under a plain
  A_DTS track.
- PgsParser is now stateful: pairs display PCS with the following
  empty PCS to compute a duration. Frame::duration_ns + PesFrame::duration_ns
  carry it through; MkvMuxer::write_frame gains a final Option<u64>
  parameter that emits BlockGroup + BlockDuration when set. Fixes
  subtitle bitmaps lingering past their intended end-time.

README.md

@@ -18,7 +18,7 @@ Part of the [freemkv](https://github.com/freemkv) project.
 
 ```toml
 [dependencies]
-libfreemkv = "0.18"
+libfreemkv = "0.25"
 ```
 
 ## Quick Start
@@ -56,8 +56,7 @@ output.finish()?;
 For damaged discs the library exposes two flat verbs — `Disc::sweep` for the
 forward Pass 1 and `Disc::patch` for retrying bad ranges. The library never
 loops; the multipass policy is the caller's job. See
-[`docs/rip-recovery.md`](docs/rip-recovery.md) and the design notes in
-`(internal)/memory/0_18_redesign.md`.
+[`docs/rip-recovery.md`](docs/rip-recovery.md).
 
 ```rust
 use libfreemkv::{SweepOptions, PatchOptions};