Cirrhy 0.2.3

Prebuilt binaries for Cirrhy 0.2.3, packaged by CI from this tag.
Honest labels, as ever:

• Linux (-linux-x64.tar.gz) — self-contained bundle; untar
  and run ./cirrhy. For a proper taskbar icon, run
  tool/install-linux.sh from a source checkout.
• Android (-android.apk) — debug-signed for now: installs
  on any device with developer mode, and will be replaced by a
  properly signed build once one exists.
• macOS (-macos-universal.zip) — unsigned and not
  notarized; first launch via right-click → Open.
• Windows (-windows-x64.zip) — compiles and packages in CI,
  but this target has not yet been tested by hand. Reports welcome.
• iOS — no artifact: an installable build needs your own
  signing; the README's "macOS and iOS" section is the way.

sha256sums.txt covers every file above.

What's Changed

• release.sh: bump appVersion too, and run the suite before pushing by @lorands in #9

Full Changelog: v0.2.1...v0.2.3