add setting hierachy for folders

[stop50]

This mostly makes mostsense when the feature to have multiple levels of folders have been implemented.

When we have mutiple levels it makes more sense to use the upper folder settings for the default.

in an structure like this:

Archive/
- 2024/
- - mozilla
- 2025/
- - mozilla/

it would be nice to set the visibility of Archive/2024 to off without needing to change the visibility of Archive/2024/mozilla.

[Jon]

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