♻️ 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-agda.min.js

@@ -1 +0,0 @@
-!function(t){t.languages.agda={comment:/\{-[\s\S]*?(?:-\}|$)|--.*/,string:{pattern:/"(?:\\(?:\r\n|[\s\S])|[^\\\r\n"])*"/,greedy:!0},punctuation:/[(){}⦃⦄.;@]/,"class-name":{pattern:/((?:data|record) +)\S+/,lookbehind:!0},function:{pattern:/(^[ \t]*)(?!\s)[^:\r\n]+(?=:)/m,lookbehind:!0},operator:{pattern:/(^\s*|\s)(?:[=|:∀→λ\\?_]|->)(?=\s)/,lookbehind:!0},keyword:/\b(?:Set|abstract|constructor|data|eta-equality|field|forall|hiding|import|in|inductive|infix|infixl|infixr|instance|let|macro|module|mutual|no-eta-equality|open|overlap|pattern|postulate|primitive|private|public|quote|quoteContext|quoteGoal|quoteTerm|record|renaming|rewrite|syntax|tactic|unquote|unquoteDecl|unquoteDef|using|variable|where|with)\b/}}(Prism);