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/remark-gfm/lib/index.js

@@ -0,0 +1,41 @@
+/**
+ * @import {Root} from 'mdast'
+ * @import {Options} from 'remark-gfm'
+ * @import {} from 'remark-parse'
+ * @import {} from 'remark-stringify'
+ * @import {Processor} from 'unified'
+ */
+
+import {gfmFromMarkdown, gfmToMarkdown} from 'mdast-util-gfm'
+import {gfm} from 'micromark-extension-gfm'
+
+/** @type {Options} */
+const emptyOptions = {}
+
+/**
+ * Add support GFM (autolink literals, footnotes, strikethrough, tables,
+ * tasklists).
+ *
+ * @param {Options | null | undefined} [options]
+ *   Configuration (optional).
+ * @returns {undefined}
+ *   Nothing.
+ */
+export default function remarkGfm(options) {
+  // @ts-expect-error: TS is wrong about `this`.
+  // eslint-disable-next-line unicorn/no-this-assignment
+  const self = /** @type {Processor<Root>} */ (this)
+  const settings = options || emptyOptions
+  const data = self.data()
+
+  const micromarkExtensions =
+    data.micromarkExtensions || (data.micromarkExtensions = [])
+  const fromMarkdownExtensions =
+    data.fromMarkdownExtensions || (data.fromMarkdownExtensions = [])
+  const toMarkdownExtensions =
+    data.toMarkdownExtensions || (data.toMarkdownExtensions = [])
+
+  micromarkExtensions.push(gfm(settings))
+  fromMarkdownExtensions.push(gfmFromMarkdown())
+  toMarkdownExtensions.push(gfmToMarkdown(settings))
+}