Fix logout (add missing nginx auth proxy) + show name/email in sidebar footer

The /cashup/api/auth/ → central auth nginx block was missing, so the logout
POST was hitting the app backend and returning 404 — cookie never cleared,
user stayed logged in. Also removes the stale navigate('/login') call and
shows name + email in the sidebar footer instead of name in the header.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/nginx.conf

@@ -25,6 +25,14 @@ server {
         try_files $uri =404;
     }
 
+    location /cashup/api/auth/ {
+        proxy_pass http://10.10.10.101:3001/api/auth/;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        add_header Cache-Control "no-store";
+    }
+
     location /cashup/api/ {
         proxy_pass http://backend:3001/api/;
         proxy_set_header Host $host;