fix: portfolio API nginx 라우팅 수정 (trailing slash 없이도 매칭)

/api/portfolio/ → /api/portfolio 로 변경하여
trailing slash 미포함 요청도 stock-lab으로 정상 프록시되도록 수정

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

nginx/default.conf

@@ -74,14 +74,14 @@ server {
 	proxy_pass http://stock-lab:8000/api/trade/;
   }
 
-  # portfolio API (Stock Lab)
-  location /api/portfolio/ {
+  # portfolio API (Stock Lab) — trailing slash 유무 모두 매칭
+  location /api/portfolio {
 	proxy_http_version 1.1;
 	proxy_set_header Host $host;
 	proxy_set_header X-Real-IP $remote_addr;
 	proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
 	proxy_set_header X-Forwarded-Proto $scheme;
-	proxy_pass http://stock-lab:8000/api/portfolio/;
+	proxy_pass http://stock-lab:8000/api/portfolio;
   }