feat(tkds): 독립 대시보드 서비스 분리 (tkds.technicalkorea.net)

대시보드를 gateway(tkfb)에서 분리하여 독립 서비스 tkds로 이동.
- tkds/web: nginx + dashboard.html 신규 서비스 (port 30780)
- gateway: /login 복원, /dashboard → tkds 301 리다이렉트
- 전체 시스템 getLoginUrl() → tkds.technicalkorea.net/dashboard로 변경

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

system2-report/web/js/api-base.js

@@ -53,9 +53,9 @@ if ('serviceWorker' in navigator) {
     var hostname = window.location.hostname;
     var t = Date.now();
     if (hostname.includes('technicalkorea.net')) {
-      return window.location.protocol + '//tkfb.technicalkorea.net/login?redirect=' + encodeURIComponent(window.location.href) + '&_t=' + t;
+      return window.location.protocol + '//tkds.technicalkorea.net/dashboard?redirect=' + encodeURIComponent(window.location.href) + '&_t=' + t;
     }
-    return window.location.protocol + '//' + hostname + ':30000/login?redirect=' + encodeURIComponent(window.location.href) + '&_t=' + t;
+    return window.location.protocol + '//' + hostname + ':30780/dashboard?redirect=' + encodeURIComponent(window.location.href) + '&_t=' + t;
   };
 
   window.clearSSOAuth = function() {