Is the father who died in the operating room after reciting the Shahada considered a martyr, and what is the interpretation of the abundance of sparrows in the mosque at Dhuhr prayer on the day of his burial?

We do not know the interpretation of what the birds did when prayers were offered for your father. However, witnessing him [saying it] at death is a sign of good tidings, for the Prophet, peace and blessings be upon him, said: "Whoever’s last words are ‘There is no god but Allah’ will enter Paradise." To answer the question "Did he die as a martyr?" please refer to the mentioned fatwas.