fix: Add nixpacks configuration for Astro deployment

dealplustech-astro/node_modules/astro/dist/runtime/server/util.js

@@ -0,0 +1,19 @@
+function isPromise(value) {
+  return !!value && typeof value === "object" && "then" in value && typeof value.then === "function";
+}
+async function* streamAsyncIterator(stream) {
+  const reader = stream.getReader();
+  try {
+    while (true) {
+      const { done, value } = await reader.read();
+      if (done) return;
+      yield value;
+    }
+  } finally {
+    reader.releaseLock();
+  }
+}
+export {
+  isPromise,
+  streamAsyncIterator
+};