chore: release v0.3.8

[github-actions]

🤖 New release

• sendspin: 0.3.7 -> 0.3.8 (✓ API compatible changes)

Changelog

0.3.8 - 2026-10-15

Fixed

• (audio) support unsigned 24-bit output (#107)
• hold sync corrections while a cold output stream's delay settles (#103)

Other

• cover startup synchronization correction transitions (#106)

Fixed

• Stop a freshly opened output stream from being corrected at up to 4% speed
  for several seconds after playback starts. On some backends (observed with
  ALSA over PulseAudio/PipeWire) the reported output delay of a cold stream
  overshoots by a few hundred milliseconds and then relaxes while the audio
  plays gaplessly, and the sync error moves with it. Corrections are now held
  back until 500ms observation-window floors stay within a 10ms range over
  a baseline window and two seconds of comparisons, independent of callback
  size (capped at 10s after playback starts). Speed corrections are limited to
  0.5% for the first 20s after a start. Callback gaps of 500ms or more discard
  settling evidence. The all-time delta floor used for reanchors is re-seeded
  from the observed floor each time the delay settles.

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