What is the ruling on a financial partnership that is repaid over four years annually, with a fixed percentage of the profits paid to the financier throughout the repayment period, and then the financier recovers the full capital along with the agreed-upon profits at the end of the term?

The transaction mentioned could be a loan or a Mudarabah (definition) (profit-sharing partnership). If it is intended to be a valid Mudarabah, then the principal amount should not be guaranteed, so that the capital provider bears the loss of their capital, and the Mudarib (investing partner) bears the loss of their effort. It appears to be a loan rather than a Mudarabah, as the full amount is repaid in installments with a profit percentage calculated based on the original principal. To correct it as a Mudarabah, its conditions must be adhered to, the most important of which is not guaranteeing the principal.