How can the revelation of the Qur’an in seven ahruf be reconciled with the existence of ten qira’at, with each qari’ having two rawiyan, and what are the shadhdhah and da’ifah readings?

The "Seven Ahruf" (seven modes/letters) are not the same as the seven widely transmitted recitations mentioned in the Matn al-Shatibiyyah. A recitation is not considered part of the Qur’an unless it has been transmitted widely (mutawatir). If its chain of transmission is sound but it has not been widely transmitted, it is considered a "shadhdh" (anomalous) recitation; it is not permissible to recite with it in prayer, though rulings can be derived from it. As for a weak recitation, it has neither been widely transmitted nor does it have a sound chain of transmission; the Qur’an is not recited with it, nor is anything derived from it.