Does Shawkani's statement regarding the invalidity of prayer due to impurity include impurity on the body, clothes, and place of prayer, and is the prayer of one who has experienced pre-seminal fluid discharge and has not washed his penis invalid?

The cure for obsessive thoughts is to ignore them and turn away from them. No matter how much you think about them and dwell on them, they will not leave you. If you ignore them and turn away from them, Allah will remove them from you. The madhhab (definition) of Ash-Shawkani is that avoiding impurity is obligatory, not a condition for the validity of prayer. So, whoever prays while being contaminated with impurity, his prayer is valid, though he incurs sin. The commands to remove impurity, in his view, indicate obligation, not conditionality. We advise you to get rid of these obsessive thoughts because they are a great door to evil.