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/cli/info/infra/bun-package-manager.d.ts

@@ -0,0 +1,5 @@
+import type { PackageManager } from '../definitions.js';
+export declare class BunPackageManager implements PackageManager {
+    readonly name: string;
+    getPackageVersion(): Promise<string | undefined>;
+}