Update dashboard community links to use env vars, add deploy configs

- Dashboard community links now use .env values like community page
- Removed hardcoded social media URLs from dashboard
- Added deploy folder with nginx and systemd service configs
- Moved linktree page to public route
- Various backend and auth context updates

frontend/src/app/(public)/page.tsx

@@ -97,7 +97,7 @@ export default function HomePage() {
                 <div className="space-y-4">
                   <div className="relative rounded-card h-32 flex items-center justify-center overflow-hidden">
                     <Image
-                      src="/images/2026-01-29 13.10.26.jpg"
+                      src="/images/2026-01-29 13.10.08.jpg"
                       alt="Language exchange event"
                       fill
                       sizes="(max-width: 1024px) 50vw, 25vw"