♻️ 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
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✅ 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/mdast-util-from-markdown/index.d.ts

@@ -1,23 +0,0 @@
-export type {Encoding, Token, Value} from 'micromark-util-types'
-export type {
-  CompileContext,
-  CompileData,
-  Extension,
-  Handles,
-  Handle,
-  OnEnterError,
-  OnExitError,
-  Options,
-  Transform
-} from './lib/types.js'
-export {fromMarkdown} from './lib/index.js'
-
-declare module 'micromark-util-types' {
-  interface TokenTypeMap {
-    listItem: 'listItem'
-  }
-
-  interface Token {
-    _spread?: boolean
-  }
-}