refactor: Move nix outside of .config dir

Technically not a config but a compose file, so I think it's better to
have outside of `.config` dir

.config/nix/users/ziro/darwin.nix

@@ -1,50 +0,0 @@
-{ pkgs, pkgs-unstable, config, vars, lib, ... }:
-
-{
-  home.homeDirectory = "/Users/ziro";
-  home.packages = lib.mkAfter
-    [
-      pkgs.casks.vscodium
-    ];
-
-  programs.browserpass = {
-    enable = true;
-    browsers = [ "brave" "chrome" ];  # Arc and Chrome share the same `Application Support` dir, not sure why tbh.
-  };
-
-  home.file."Library/Application Support/Floorp/native-messaging-hosts/passff.json".source = "${pkgs.passff-host}/share/passff-host/passff.json";
-
-  # Swap CapsLock with Esc for better vi-mode experience.
-  launchd.agents.CapsEscSwap = {
-    enable = true;
-    config = {
-      ProgramArguments = [
-        "/usr/bin/hidutil"
-        "property"
-        "--set"
-        ''{"UserKeyMapping":[{"HIDKeyboardModifierMappingSrc":0x700000039,"HIDKeyboardModifierMappingDst":0x700000029},{"HIDKeyboardModifierMappingSrc":0x700000029,"HIDKeyboardModifierMappingDst":0x700000039}]}''
-      ];
-      RunAtLoad = true;
-    };
-  };
-
-  home.sessionVariables.MOZ_LEGACY_PROFILES = 1;
-
-  home.activation.applications = let
-    env = pkgs.buildEnv {
-      name = "home-applications";
-      paths = config.home.packages;
-      pathsToLink = "/Applications";
-    };
-  in lib.hm.dag.entryAfter [ "writeBoundary" ] ''
-    echo "setting up ${config.home.homeDirectory}/Applications..." >&2
-    rm -rf "${config.home.homeDirectory}/Applications/Nix Home Manager Apps"
-    mkdir -p "${config.home.homeDirectory}/Applications/Nix Home Manager Apps"
-    find ${env}/Applications -maxdepth 1 -type l -exec readlink '{}' + |
-      while read src; do
-        app_name=$(basename "$src")
-        echo "copying $src" >&2
-        ${pkgs.mkalias}/bin/mkalias "$src" "${config.home.homeDirectory}/Applications/Nix Home Manager Apps/$app_name"
-      done
-  '';
-}