Is the daily Istikhara supplication, as mentioned, rooted in Islamic law, or is it considered an innovation?

This daily supplication has not been narrated from the Prophet (peace be upon him), and its meaning is not objectionable. However, persisting in it daily makes it an additional innovation (bid'ah) by equating something not sunnah with something that is sunnah. The Prophet (peace be upon him) legislated the Salatul-Istikhara (prayer for guidance) when one is concerned about a matter, and not without need. So, if Salatul-Istikhara is not legislated for no reason, then this daily supplication, in this manner, is even more deserving of not being legislated.