修复了有旧会话信息时，无法自动重置会话的bug

frontend/Web/sessioninit.js

@@ -0,0 +1,15 @@
+var SessionReadyEvent = new Event('SessionReady');
+(async () => {
+  if(session_token==null||outhentication_key==null||operation_count==null){
+    let tmp_channel=generateRandomString(10);
+    let ret=await RawRequest('#OpenSession '+tmp_channel);
+    operation_count=0;
+    session_token=ret.split('\n')[1].split(' ')[0];
+    outhentication_key=ret.split('\n')[1].split(' ')[1];
+    localStorage.setItem("session_token", session_token);
+    localStorage.setItem("outhentication_key", outhentication_key);
+    localStorage.setItem("operation_count", operation_count);
+  }
+  document.dispatchEvent(SessionReadyEvent);
+  console.log("Sent event Session Ready");
+})();