XDG_CONFIG_HOME support on MacOS

[jag-k]

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• [x] I have searched the documentation and believe that my question is not covered.

Issue

Please add support $XDG_CONFIG_HOME env var for config on MacOS

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[ErikBjare]

We are using https://github.com/platformdirs/platformdirs and https://github.com/djc/appdirs-rs to get platform directories. We do not want to implement custom logic on top of it, if we can help it. See here for more: https://docs.activitywatch.net/en/latest/directories.html

If you want an alternative storage location for the config folder on macOS, I suggest you use symlinks.