Add Tencent cloud push (video introduction), support preview email before sending, and visually see the status of Tencent cloud push, whether each email is successfully delivered, whether it is read, whether the link in the email is clicked, whether it is complained, and whether it is blocked.
Collect and optimize the return interface to avoid misunderstanding caused by the progress bar.
HTTP send missing file prompt.
Correction: the sending progress is inconsistent with the actual sending progress due to the abnormal shutdown of the computer.
Correction: the mass mail sending task was not stopped when the computer was turned off, resulting in the inconsistency between the sending progress and the actual sending progress.