fix(admin): index.html 与 assets 缓存策略，避免发版后白屏

Made-with: Cursor

deploy/admin/default.conf

@@ -3,6 +3,20 @@ server {
   listen 80;
   root /usr/share/nginx/html;
   index index.html;
+
+  # 发版后勿长期缓存入口，否则浏览器保留旧 index.html、却拉新 chunk 名 → 白屏
+  location = /index.html {
+    add_header Cache-Control "no-cache, no-store, must-revalidate";
+    expires -1;
+  }
+
+  location ^~ /assets/ {
+    try_files $uri =404;
+    access_log off;
+    expires 7d;
+    add_header Cache-Control "public, immutable";
+  }
+
   location / {
     try_files $uri $uri/ /index.html;
   }