Does Sharia prohibit placing shoes in a designated area for them in front of worshippers, and what is the appropriate jurisprudential ruling in the case of repeated shoe theft in the mosque?

The place for one's sandals is between the feet, or to the left if there is no one on the worshipper's left, or behind the worshipper. If this is not possible, there is no impediment to placing them in front of the worshipper during prayer, provided there is no harm to others. There is also no impediment to making something in which the worshippers' shoes can be placed in front of them, due to the benefit of avoiding placing sandals directly on the mosque's carpets, in addition to removing the distraction of thinking about them.