Magneto v0.9.4

Windows installer now quits a running Magneto by itself.

• Updating or uninstalling no longer requires quitting Magneto first; the installer stops the app and the daemon before touching files

Install

• Windows: Magneto_0.9.4_x64-setup.exe. Unsigned, so SmartScreen
  warns on first run ("More info" then "Run anyway"), and Windows asks once
  to allow network access for the daemon.
• Linux: .deb, .rpm, or .AppImage. The AppImage needs fuse3
  (preinstalled on most desktops; otherwise run with
  --appimage-extract-and-run).
• macOS: build from source for now.

This is still an early release. Expect rough edges.
Thank you.