fix(net): validate wire frames and coalesce reconnects

cocoscreator_projects/framework-tests/helpers/fake-transport.ts

@@ -11,14 +11,16 @@ export class FakeTransport implements Transport {
   private closeCb?: () => void;
   private pending: Array<() => void> = [];
   private closed = false;
-  private connectFailure: unknown = null;
+  private hasConnectFailure = false;
+  private connectFailure: unknown;
 
   connect(url: string): void {
     this.connectCalls++;
     this.url = url;
-    if (this.connectFailure !== null) {
+    if (this.hasConnectFailure) {
       const error = this.connectFailure;
-      this.connectFailure = null;
+      this.hasConnectFailure = false;
+      this.connectFailure = undefined;
       throw error;
     }
     this.pending.push(() => this.openCb?.());
@@ -35,7 +37,10 @@ export class FakeTransport implements Transport {
   onClose(cb: () => void): void { this.closeCb = cb; }
 
   /** 测试侧：令下一次 connect 同步失败。 */
-  failNextConnect(error: unknown): void { this.connectFailure = error; }
+  failNextConnect(error: unknown): void {
+    this.hasConnectFailure = true;
+    this.connectFailure = error;
+  }
 
   /** 测试侧：模拟服务器推一帧给客户端。 */
   serverPush(frame: string): void { this.pending.push(() => this.msgCb?.(frame)); }