♻️ Restructure: Move Astro to repository root

BREAKING CHANGE: Astro project is now at repository root
- Removed dealplustech-astro subdirectory
- Moved all Astro files to root
- Updated PostCSS config to .cjs
- Removed old Next.js files

✅ 11 pages built successfully
✅ Cookie consent banner included
✅ Privacy/Terms links in footer
✅ Ready for Easypanel deployment (no root dir needed)

Migration path:
- Old structure: /dealplustech-astro/
- New structure: / (root)

dealplustech-astro/node_modules/nlcst-to-string/lib/index.d.ts

@@ -1,13 +0,0 @@
-/**
- * Get the text content of a node or list of nodes.
- *
- * Prefers the node’s plain-text fields, otherwise serializes its children, and
- * if the given value is an array, serialize the nodes in it.
- *
- * @param {Array<Nodes> | Nodes} value
- *   Node or list of nodes to serialize.
- * @returns {string}
- *   Result.
- */
-export function toString(value: Array<Nodes> | Nodes): string;
-export type Nodes = import('nlcst').Nodes;