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/mdast-util-to-hast/lib/handlers/root.js

@@ -0,0 +1,22 @@
+/**
+ * @import {Parents as HastParents, Root as HastRoot} from 'hast'
+ * @import {Root as MdastRoot} from 'mdast'
+ * @import {State} from '../state.js'
+ */
+
+/**
+ * Turn an mdast `root` node into hast.
+ *
+ * @param {State} state
+ *   Info passed around.
+ * @param {MdastRoot} node
+ *   mdast node.
+ * @returns {HastParents}
+ *   hast node.
+ */
+export function root(state, node) {
+  /** @type {HastRoot} */
+  const result = {type: 'root', children: state.wrap(state.all(node))}
+  state.patch(node, result)
+  return state.applyData(node, result)
+}