feat: Upgrade to Astro with full PDPA compliance

PDPA Features:
✅ Cookie consent banner
✅ Consent logging API
✅ Admin dashboard
✅ Privacy Policy
✅ Terms & Conditions

Technical:
✅ Astro 5.x + Tailwind v4
✅ Docker on port 80
✅ SQLite database
✅ 15 pages built

Ready for Easypanel deployment.

node_modules/postcss/lib/stringify.d.ts

@@ -0,0 +1,9 @@
+import { Stringifier } from './postcss.js'
+
+interface Stringify extends Stringifier {
+  default: Stringify
+}
+
+declare const stringify: Stringify
+
+export = stringify