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/@astrojs/markdown-remark/dist/highlight.d.ts

@@ -0,0 +1,16 @@
+import type { Root } from 'hast';
+type Highlighter = (code: string, language: string, options?: {
+    meta?: string;
+}) => Promise<Root | string>;
+export declare const defaultExcludeLanguages: string[];
+/**
+ * A hast utility to syntax highlight code blocks with a given syntax highlighter.
+ *
+ * @param tree
+ *   The hast tree in which to syntax highlight code blocks.
+ * @param highlighter
+ *   A function which receives the code and language, and returns the HTML of a syntax
+ *   highlighted `<pre>` element.
+ */
+export declare function highlightCodeBlocks(tree: Root, highlighter: Highlighter, excludeLanguages?: string[]): Promise<void>;
+export {};