Do not report TTFD span with DEADLINE_EXCEEDED status

### Problem Statement

Hi!

We started reporting TTFD for one of our screens, and we noticed that the SDK also attaches the TTFD span to all other screens with `DEADLINE_EXCEEDED` status. Since our pricing now depends on span count, it would be better not to attach it to all transactions, because implementing the TTFD reporting for every screen requires additional development.


I think that we can fix it on our side with a custom `EventProcessor` that will remove such spans, but please consider improving it on the SDK's side.

Thank you!

### Solution Brainstorm

_No response_

未指定檔案、測試或進入點。首先定位 TTFD span 的建立位置，以及 SDK 如何處理 DEADLINE_EXCEEDED 交易。完成的標誌是：TTFD span 不會附加到狀態為 DEADLINE_EXCEEDED 的無關交易上，並且對變更後的行為有測試涵蓋。

由索引模型根據 Issue 內容生成。