refactor(flake-parts): initial flake-parts configuration

inputs/home/modules/console/utility/nixIndex/default.nix

@@ -0,0 +1,38 @@
+{ pkgs, config, lib, ... }:
+let
+  cfg = config.homeModules.console.utility.nixIndex;
+  update-script = pkgs.writeShellApplication {
+    name = "fetch-nix-index-database";
+    runtimeInputs = with pkgs; [ wget coreutils ];
+    text = ''
+      filename="index-x86_64-linux"
+      mkdir -p ~/.cache/nix-index
+      cd ~/.cache/nix-index
+      wget -N "https://github.com/Mic92/nix-index-database/releases/latest/download/$filename"
+      ln -f "$filename" files
+    '';
+  };
+in
+{
+  config = lib.mkIf cfg.enable {
+    programs.nix-index.enable = true;
+
+    systemd.user.services.nix-index-database-sync = {
+      Unit = { Description = "fetch mic92/nix-index-database"; };
+      Service = {
+        Type = "oneshot";
+        ExecStart = "${update-script}/bin/fetch-nix-index-database";
+        Restart = "on-failure";
+        RestartSec = "5m";
+      };
+    };
+    systemd.user.timers.nix-index-database-sync = {
+      Unit = { Description = "Automatic github:mic92/nix-index-database fetching"; };
+      Timer = {
+        OnBootSec = "10m";
+        OnUnitActiveSec = "24h";
+      };
+      Install = { WantedBy = [ "timers.target" ]; };
+    };
+  };
+}