Provide homeManagerModule as a flake output

[ilkecan]

Main change is the added home-manager module, which can be used like

    neuron = {
      enable = true;
      notesDirectory = "/home/${name}/zettelkasten";
      prettyUrls = true;
    };

See divnix/digga#106 (comment) for pointers about how to add a home-manager module from a flake to imports.

I also removed the unnecessary app definitions, since by default nix run will try the packages with the same name. App definitions are mainly useful if there are multiple binaries or you want to name them differently.

[ilkecan]

Also nix flake show currently produces an error like

error: a 'aarch64-linux' with features {} is required to build '/nix/store/0a5kf39y7vpnbgcnis3gp3spbdpndvij-cabal2nix-neuron.drv', but I am a 'x86_64-linux' with features {benchmark, big-parallel, kvm, nixos-test}

But I couldn't fix this easily. In general, I think the nix code is unnecessarily complex. You said nix-thunk should be removed in favour of flake inputs in the previous PR. Does that mean https://github.com/srid/neuron/blob/master/nixpkgs.nix should be removed? I can try to work on these in a separate PR.

[srid]

You said we nix-thunk should be removed in favour of flake inputs in the previous PR. Does that mean https://github.com/srid/neuron/blob/master/nixpkgs.nix should be removed? I can try to work on these in a separate PR.

Yes, that would be awesome. You can use https://github.com/srid/emanote for inspiration (by the way, emanote is the successor project to neuron).