KnockKnock items don't match MacOS Ventura's Login Items

[jguerin]

My Mac warned me that a background launch agent was installed and it shows up in the UX, but it's not reflected in KnockKnock. Some of the items were stale and just a result of the plist being left behind, but the associated agent was deleted. In those cases, it'd be great for KnockKnock to show these plist items so that they can be removed.

However, there's still some items showing up in System Settings that I cannot find on disk in well-known locations, and KnockKnock also doesn't show anything.

So, there's two asks:

1. KnockKnock should reflect the same items as System Settings
2. KnockKnock should still display plist entries, even if the agent they're pointing to no longer exists

[objective-see]

Version 2.4, added a new plugin: "Background Task Management", that now mimics/matches macOS "Login Item" UI.