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Feature Request Description

During uninstall, decky-loader calls stop() which triggers _unload(), but from my conversations in Discord, I can't rely on _unload() to be 1:1 with uninstall (i.e. it may be triggered at other times in the plugin lifecycle).

My plugin installs a systemd service when it's loaded, but since there's no reliable way to tap into decky's uninstall mechanism, a user uninstalling my plugin may be surprised to find that it's still operating behind the scenes.

This request is to add an uninstall function to the Plugin interface that is called after stop() and before deletion of the plugin directory.

Further Description

No response