What is the Sharia ruling regarding a farming partnership problem where the partner has not repaid the agreed-upon amount after six years, and who is responsible for paying Zakat on the capital invested during these years, and is Zakat obligatory on artworks displayed for sale, and how is its Zakat calculated, and who is responsible for the Zakat on the value of the frames?

"Paying money to buy provisions and seeds for cultivation, with the profit to be shared between you and the landowner, constitutes an invalid partnership. Everything resulting from it belongs to you. You bear the loss if it occurs without negligence on the worker's part, and you must pay him a fair wage (ujrat al-mithl). The money you paid is not subject to zakat (definition) unless a full year has passed while it is at the threshold (nisab (definition)). If the owner of the money is a procrastinator, zakat is not due until one year after the money is received. Agricultural machinery and materials purchased for tilling are not subject to zakat. Regarding the paintings, the value of the frames and the selling fee should have been agreed upon in advance. He is entitled to a fair wage (ujrat al-mithl) for them. Zakat is not due on the paintings themselves because they are not trade goods. Zakat becomes due on their value if they are sold and a full year has passed while the amount is at the threshold (nisab)."