Does the Prophet's (peace be upon him) approval of reciting Surat Al-Ikhlas in the last Rak'ah of the Fajr prayer make it a Sunnah, and is it recited in other prayers besides Fajr?

The Prophet's approval of a Companion's action makes it a Sunnah. It is permissible to recite Surat Al-Ikhlas for one who is overcome by love for it. However, for one who makes it a regular devotional recitation (wird) without this meaning, the Prophet's guidance is more perfect than the Companion's guidance.