♻️ 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

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✅ Ready for Easypanel deployment (no root dir needed)

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

dealplustech-astro/node_modules/prismjs/components/prism-ebnf.min.js

@@ -1 +0,0 @@
-Prism.languages.ebnf={comment:/\(\*[\s\S]*?\*\)/,string:{pattern:/"[^"\r\n]*"|'[^'\r\n]*'/,greedy:!0},special:{pattern:/\?[^?\r\n]*\?/,greedy:!0,alias:"class-name"},definition:{pattern:/^([\t ]*)[a-z]\w*(?:[ \t]+[a-z]\w*)*(?=\s*=)/im,lookbehind:!0,alias:["rule","keyword"]},rule:/\b[a-z]\w*(?:[ \t]+[a-z]\w*)*\b/i,punctuation:/\([:/]|[:/]\)|[.,;()[\]{}]/,operator:/[-=|*/!]/};