Termuna 0.2.3

Changelog: https://termuna.com/changelog/

Before publishing: build and attach the macOS app, which
cannot be built here (Apple's SDK is not redistributable):

scripts/build-macos-app.sh
cp target/macos/Termuna-0.2.3-arm64.tar.gz Termuna-arm64.tar.gz
gh release upload v0.2.3 -R termuna/termuna \
  target/macos/Termuna-0.2.3-arm64.tar.gz Termuna-arm64.tar.gz

Then download one asset per platform and publish.

After publishing, sign the update manifest (ADR 0009).
Installed apps check it once a day and refuse anything this
key did not sign, so until it is uploaded they are told there
is nothing new:

scripts/sign-release.sh v0.2.3

It runs by hand, on your machine, and it runs LAST: the
signing key must never be a CI secret (that is the whole
point of signing), and the manifest hashes every artifact,
including the macOS one above.