feat: add flake output

flake.lock

@@ -0,0 +1,25 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1655361562,
+        "narHash": "sha256-chPaIIhmdL6jdZWpf/K6yQCsuBNOYuMqbJsNpLfrdTE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0b59d075675dc28bf9ebab466033280096c8d4fe",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,8 @@
+{
+  description = "NixOS VSCode server";
+
+  outputs = { self, nixpkgs }: {
+    nixosModule = import ./modules/vscode-server;
+    nixosModules.default = self.nixosModule;
+  };
+}