[draft] add direnv, nix configs, and uv lock file

Author: yvan-sraka

.envrc

@@ -0,0 +1,2 @@
+layout python
+# use nix

shell.nix

@@ -0,0 +1,4 @@
+{ pkgs ? import <nixpkgs> {} }:
+  pkgs.mkShell {
+    nativeBuildInputs = with pkgs.buildPackages; [ gcc openssl pkg-config ];
+}