Is it permissible to repeat the prayer and ablution due to doubt, what is the ruling on involuntary thoughts during prayer and lack of devotion, and what is the description of the prostration of forgetfulness for doubt and other reasons?

If the doubt is due to whisperings (waswasah), the one afflicted by waswasah should not repeat what they doubted, nor pay attention to the whisperings, nor perform the prostration of forgetfulness (sujud as-sahw) because of them. Likewise, if doubt occurs after completing an act of worship, it should be disregarded. However, if the worshipper doubts the number of rak'ahs during the prayer, they should base it on the lesser number and perform the prostration of forgetfulness. If, during ablution (wudu'), they doubt having washed a limb, they should wash it and whatever comes after it. Thoughts during prayer do not invalidate it, and it is not recommended to repeat the prayer due to a lack of devotion (khushu'). The prostration of forgetfulness for doubt is performed before the salutation (taslim), but if performed after it, it is still valid. It consists of two prostrations. One says takbir after the tashahhud, prostrates, and recites what is recited in the prostration of prayer. Then one rises and says takbir, prostrates a second time, says takbir, then rises, says takbir, and gives two salutations.