wavpack: update to 5.9.0

wavpack: update to 5.9.0

Release 5.9.0 (January 16, 2026):
 * added: new feature to wvtag to copy tags from one WavPack file
   to another
 * improved: minor tweaks to the new DNS (dynamic noise shaping)
   algorithm
 * improved: better handling of specific non-standard WAV and AIFF
   files
 * improved: added CI (GitHub Actions) and fixed a few minor build
   issues
 * fixed: --pause option failed in many situations (Windows-only)
 * fixed: issues related to encoding from an unknown length
   (e.g., pipes)
 * fixed: several fuzzer-revealed issues related to multithreading
 * fixed: potential buffer overruns in WavpackOpenRawDecoder()

Link: https://github.com/dbry/WavPack/blob/5.9.0/NEWS
Signed-off-by: Daniel Golle <redacted>