What is the ruling on holding Friday prayer twice in one mosque with two different imams, and do circumstances such as limited space or other reasons justify this, bearing in mind the existence of other places for Friday prayer and the jurisprudential disagreement regarding the issue of multiple Friday prayers in one city?

Establishing two Jumu'ah prayers in one town was not known during the time of the Companions. The purpose of Jumu'ah is for believers to gather, be admonished, and for hearts to be unified. Limiting it to one Jumu'ah achieves these objectives.

The Malikis, Shafi'is, Hanbalis, and the most authoritative view among the Hanafis, all hold that it is not permissible to establish more than one Jumu'ah prayer in a town without a need. If Jumu'ah prayers are multiplied without need, the prayer of those who prayed later becomes invalid, and they must repeat the Dhuhr prayer.

As for establishing two Jumu'ah prayers in a single mosque, this is even more prohibited and has no basis in Islam.