Migrate to snowfall lib

overlays/yarn-berry/adefault.nix

@@ -0,0 +1,12 @@
+{ ... }:
+final: prev: {
+  yarn-berry = prev.yarn-berry.overrideAttrs (old: rec {
+    version = "3.6.3";
+    src = prev.fetchFromGitHub {
+      owner = "yarnpkg";
+      repo = "berry";
+      rev = "@yarnpkg/cli/${version}";
+      hash = "sha256-5QEnFalOEMs1bKYDYpFGnF1YwiGuW3ZxstyJAjz1/KQ=";
+    };
+  });
+}