refactor: Move Astro to root, use PORT env (default 80), allow all hosts

- Move Astro files from dealplustech-astro/ to project root
- Update Dockerfile: PORT environment variable (default 80)
- Add vite.config.ts with allowedHosts: true
- Matches nixpacks behavior for Easypanel deployment
- No hardcoded ports or domains

node_modules/astro/dist/env/errors.js

@@ -0,0 +1,16 @@
+function invalidVariablesToError(invalid) {
+  const _errors = [];
+  for (const { key, type, errors } of invalid) {
+    if (errors[0] === "missing") {
+      _errors.push(`${key} is missing`);
+    } else if (errors[0] === "type") {
+      _errors.push(`${key}'s type is invalid, expected: ${type}`);
+    } else {
+      _errors.push(`The following constraints for ${key} are not met: ${errors.join(", ")}`);
+    }
+  }
+  return _errors;
+}
+export {
+  invalidVariablesToError
+};