Adds assets/menubar-logo.png and generates AppIcon.icns (all standard sizes
via sips + iconutil) in package-app.sh, so the menubar app ships with a real
icon instead of the generic one. Info.plist already referenced AppIcon.
Icon and bundler change from @tvcsantos's #439; the unrelated tsconfig.json
change in that PR was left out.
The installer now downloads and verifies a .sha256 companion file
before extracting and launching the menubar app. Build script and
CI workflow generate the checksum alongside the zip. Adds SECURITY.md
with reporting instructions.
Addresses #215.
Removes references to future signing decisions, dollar amounts, and
star thresholds from the menubar README, the CHANGELOG, the release
workflow (its YAML comments and the auto-generated release body), and
the packaging script. The technical description stays; the 'we are
not paying for X right now' framing is out.