Exception missing in response for failed ones.

When large number of failures, no exception details present in response but only error count. The count of exceptions in response do not match failed count. That means for some failures exception objects are missing.

Documentation https://firebase.google.com/docs/reference/admin/error-handling says "Every API error is guaranteed to contain an error code and an error message" which is not the case here.

Notification is send to registration tokens of almost 2.3 million. Almost 2.2 million are success. For around 88k no exception present in response. I use firebase admin SDK 9.1.1. The method used is sendMulticast().

Sample usage:
BatchResponse response = fcmMessaging.sendMulticast(multiCastMessage, dryRun);

從 sendMulticast() 入口點開始，檢查 BatchResponse 如何表示註冊失敗的權杖，並以回報的 Firebase Admin SDK 9.1.1 行為和連結的錯誤處理文件作為背景。若可能，請重現大型批次的情況，然後確認每個失敗的權杖都有例外，且例外數量與失敗數量相符。

由索引模型根據 Issue 內容生成。