Is the alignment of rows done by the heel or the front of the foot, and is it true that Omar ibn Al-Khattab used to align the row by the heel?

Aligning rows is done by pressing shoulder to shoulder and ankle to ankle. The proof for this is the action of the Companions, as stated in Sahih al-Bukhari, where Al-Nu'man ibn Bashir said: "I saw a man among us pressing his ankle to his companion's ankle." As for whether Umar, may Allah be pleased with him, specifically aligned the rows in this manner, there is no particular text to that effect. However, his eagerness to follow the Sunnah of the Prophet, peace and blessings be upon him, is well-known, so it would not be surprising for him to apply this method, especially since the Companions were doing it in compliance with the Prophet's command, peace and blessings be upon him.