htop: write-protect entire configuration directory

[9ary]

Description

As of htop-dev/htop@5e8fc97, htop creates a new config file and renames it over home-manager's symlink. This PR works around this by moving the whole $XDG_CONFIG_HOME/htop directory into the nix store, preventing such overwrites.

Checklist

• Change is backwards compatible. (it isn't, activation will fail with Existing file '$XDG_CONFIG_HOME/htop' is in the way of '/nix/store/...-home-manager-files/.config/htop')

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

• Test cases updated/added. See example.

• Commit messages are formatted like

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  See CONTRIBUTING for more information and recent commit messages for examples.

• If this PR adds a new module

  • Added myself as module maintainer. See example.

Maintainer CC

@bjpbakker