fix: Add nixpacks configuration for Astro deployment

dealplustech-astro/node_modules/astro/dist/vite-plugin-astro/metadata.js

@@ -0,0 +1,21 @@
+function getAstroMetadata(modInfo) {
+  if (modInfo.meta?.astro) {
+    return modInfo.meta.astro;
+  }
+  return void 0;
+}
+function createDefaultAstroMetadata() {
+  return {
+    hydratedComponents: [],
+    clientOnlyComponents: [],
+    serverComponents: [],
+    scripts: [],
+    propagation: "none",
+    containsHead: false,
+    pageOptions: {}
+  };
+}
+export {
+  createDefaultAstroMetadata,
+  getAstroMetadata
+};