Release version 14.2.

Release version 14.1.

Release version 14.0.

Release version 13.1.

Add provenance attestations.

Migrate to actions/upload-artifact@v4.

The version number was increased without accounting for
backwards-incompatible changes.

Release version 12.0

Add changelog for previous commit.

Avoid deadlock when closing sync connection with unread messages.

Fix #1336.

Restore speedups.c in source distribution.