Installer can leave duplicate menu bar apps running after PerchApp path migration

[Jing-yilin]

Summary

After installing the latest release, macOS showed two Perch menu bar items.

Observed locally

Two PerchApp processes were running at the same time:

/Users/yilin/.local/share/perch/PerchApp
/Users/yilin/.local/share/perch/Perch.app/Contents/MacOS/PerchApp

perch menubar login status also still pointed at the old flat executable path:

Launch at login: enabled (/Users/yilin/.local/share/perch/PerchApp)

Expected behavior

The installer should avoid duplicate menu bar instances when upgrading/migrating from the old flat PerchApp executable path to the new Perch.app bundle path.

Suggested fix

During install/upgrade:

1. Stop all running PerchApp processes, including old flat-path instances.
2. If launch-at-login is enabled and points to the old flat executable, rewrite it to the newly installed app bundle executable.
3. Then open only the new Perch.app.

Local workaround used

perch menubar stop
perch menubar start
perch menubar login enable --app-path ~/.local/share/perch/Perch.app

This left one running process and updated launch-at-login to:

/Users/yilin/.local/share/perch/Perch.app/Contents/MacOS/PerchApp