fix: use handle instead of handle_path for WebSocket proxy

Caddyfile

@@ -13,7 +13,7 @@
     reverse_proxy /sessionserver/* backend:8080
 
     # 2. WebSocket для измерения пинга
-    handle_path /ws/ping* {
+    handle /ws/ping {
         reverse_proxy ping-helper:8081
     }