What is the ruling on renting wedding halls where alcohol is prepared, and what is the ruling on Muslims attending such weddings when invited, knowing that the alcohol is not visible in the hall but is hidden in the shared kitchen?

If the hall where the Muslim ceremony is held is separate, and alcohol is not seen in it, nor is it consumed at the Muslims' table or in their hall, then there is no harm in attending. The consumption of alcohol in another separate hall does not cause any detriment.