♻️ 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-nix.js

@@ -1,37 +0,0 @@
-Prism.languages.nix = {
-	'comment': {
-		pattern: /\/\*[\s\S]*?\*\/|#.*/,
-		greedy: true
-	},
-	'string': {
-		pattern: /"(?:[^"\\]|\\[\s\S])*"|''(?:(?!'')[\s\S]|''(?:'|\\|\$\{))*''/,
-		greedy: true,
-		inside: {
-			'interpolation': {
-				// The lookbehind ensures the ${} is not preceded by \ or ''
-				pattern: /(^|(?:^|(?!'').)[^\\])\$\{(?:[^{}]|\{[^}]*\})*\}/,
-				lookbehind: true,
-				inside: null // see below
-			}
-		}
-	},
-	'url': [
-		/\b(?:[a-z]{3,7}:\/\/)[\w\-+%~\/.:#=?&]+/,
-		{
-			pattern: /([^\/])(?:[\w\-+%~.:#=?&]*(?!\/\/)[\w\-+%~\/.:#=?&])?(?!\/\/)\/[\w\-+%~\/.:#=?&]*/,
-			lookbehind: true
-		}
-	],
-	'antiquotation': {
-		pattern: /\$(?=\{)/,
-		alias: 'important'
-	},
-	'number': /\b\d+\b/,
-	'keyword': /\b(?:assert|builtins|else|if|in|inherit|let|null|or|then|with)\b/,
-	'function': /\b(?:abort|add|all|any|attrNames|attrValues|baseNameOf|compareVersions|concatLists|currentSystem|deepSeq|derivation|dirOf|div|elem(?:At)?|fetch(?:Tarball|url)|filter(?:Source)?|fromJSON|genList|getAttr|getEnv|hasAttr|hashString|head|import|intersectAttrs|is(?:Attrs|Bool|Function|Int|List|Null|String)|length|lessThan|listToAttrs|map|mul|parseDrvName|pathExists|read(?:Dir|File)|removeAttrs|replaceStrings|seq|sort|stringLength|sub(?:string)?|tail|throw|to(?:File|JSON|Path|String|XML)|trace|typeOf)\b|\bfoldl'\B/,
-	'boolean': /\b(?:false|true)\b/,
-	'operator': /[=!<>]=?|\+\+?|\|\||&&|\/\/|->?|[?@]/,
-	'punctuation': /[{}()[\].,:;]/
-};
-
-Prism.languages.nix.string.inside.interpolation.inside = Prism.languages.nix;