What is the meaning of the tranquility, profuse sweating, smiling, fair and radiant face, swiftness of the funeral procession, and large number of mourners for a deceased person who was undergoing surgery, and do these indicate a good ending or martyrdom?

A parent's patience is a sign of goodness and love from Allah, for Allah loves the patient and gives them glad tidings of mercy and guidance. The death of a believer with a sweating forehead is a sign of a good ending. As for smiling at the time of death, there is no explicit text indicating that it signifies Allah's pleasure, but a bright and illuminated face indicates a good ending. One who dies during surgery is not explicitly a martyr, but it is hoped that they might be among them if their death involved severe hardship. Hastening the funeral is a Sunnah, and a large number of mourners is good for the deceased. The appearance of signs of a good ending is a glad tiding, but it does not necessarily guarantee entry into Paradise, and their absence does not mean a lack of righteousness.