v0.12.0

Changed

• The in-app updater now updates Arch through the AUR. On Arch (and its
  derivatives) the update prompt pastes yay -S lich-bin instead of the
  install.sh one-liner, keeping the install tracked by the user's AUR helper.
  Since yay does not know how to relaunch lich, the pasted command chains an
  explicit restart using the terminal session's own loopback credentials. Other
  distros are unchanged.

Fixed

• The app window now shows the lich icon. The frontend served no favicon,
  so the Chromium --app window fell back to a generic page icon in the
  taskbar (most visible on Windows). The app icon now ships with the frontend
  and is declared in the page head.

Added

• A one-click Restart button after a Windows/macOS self-apply. Once the
  update is downloaded and swapped in, the toast now carries a Restart
  button that relaunches lich in place instead of only telling you to restart
  by hand. It drives the same /restart in-place relaunch the Linux installer
  already uses; the button stays until you use it, since the new binary only
  takes over on the next launch.
• lich is on the AUR. yay -S lich-bin (or paru -S lich-bin) installs
  the released binary; every release now pushes the updated PKGBUILD to the
  AUR automatically.