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/env-loader.d.ts

@@ -0,0 +1,12 @@
+import type { AstroConfig } from '../types/public/index.js';
+interface EnvLoaderOptions {
+    mode: string;
+    config: AstroConfig;
+    useStatic: boolean;
+}
+export declare const createEnvLoader: (options: EnvLoaderOptions) => {
+    get: () => Record<string, string>;
+    getPrivateEnv: () => Record<string, string>;
+};
+export type EnvLoader = ReturnType<typeof createEnvLoader>;
+export {};