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/vite-plugin-astro-server/index.js

@@ -0,0 +1,9 @@
+import { createController, runWithErrorHandling } from "./controller.js";
+import { default as default2 } from "./plugin.js";
+import { handleRequest } from "./request.js";
+export {
+  createController,
+  handleRequest,
+  runWithErrorHandling,
+  default2 as vitePluginAstroServer
+};