fix: nginx 레거시 리다이렉트 tkds→tkfb 수정

/login, /dashboard 경로가 여전히 tkds.technicalkorea.net으로
302/301 리다이렉트하고 있었음. 이게 진짜 원인.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

system1-factory/web/nginx.conf

@@ -100,12 +100,12 @@ server {
         proxy_send_timeout 180s;
     }
 
-    # 레거시 /login, /dashboard → gateway(tkds) 리다이렉트
+    # 레거시 /login, /dashboard → gateway 리다이렉트
     location = /login {
-        return 302 $scheme://tkds.technicalkorea.net/dashboard$is_args$args;
+        return 302 $scheme://tkfb.technicalkorea.net/dashboard$is_args$args;
     }
     location = /dashboard {
-        return 301 $scheme://tkds.technicalkorea.net/dashboard;
+        return 301 $scheme://tkfb.technicalkorea.net/dashboard;
     }
 
     # Health check