fix: frontend browser caching issue

Disable caching for index.html and reduce static assets cache to 30d.

vite-frontend/nginx.conf

@@ -45,10 +45,18 @@ http {
 
         # 静态文件缓存
         location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg)$ {
-            expires 1y;
+            expires 30d;
             add_header Cache-Control "public, immutable";
         }
 
+        # HTML 文件不缓存
+        location ~* \.(?:htm|html)$ {
+            add_header Cache-Control "no-cache, no-store, must-revalidate";
+            add_header Pragma "no-cache";
+            add_header Expires "0";
+            try_files $uri $uri/ /index.html;
+        }
+
         # Vue Router的history模式支持
         location / {
             try_files $uri $uri/ /index.html;