Is it necessary to repeat the prayer if one finds prostatic fluid (madhy) after prayer, especially if this occurs frequently and without lust, and after urinating? And how should one perform purification and prayer, what is the ruling on congregational prayer for such a person, and what should one do with their clothes?

This is an ongoing event, like urinary incontinence, and the affected person must perform ablution for each prayer, because it is among the things that nullify ablution. If something exits from him while he is praying, he does not repeat his prayer nor does he stop it. It does not defile clothing, and he must perform ablution for the next prayer if something exits from him after the first prayer, and purify his clothes for the subsequent prayer. He should try to protect himself by wearing a guard that prevents his clothes from being soiled. He is permitted to pray with the congregation as a follower, but he is not permitted to lead the prayer in this state. He must strive to treat himself.