What is the ruling on swearing an oath to and requesting jinn to steal money or retrieve items, and is seeking the help of jinn in such matters considered major shirk?

The use of jinn in forbidden acts is judged according to what they are used for: if they are sought for help in disbelief (kufr), then it is disbelief; and if they are sought for help in sins, then it is sinful. Seeking help from a creature in what it is capable of is permissible in lawful matters and forbidden in unlawful matters. As for seeking help from a creature in what only Allah Almighty is capable of, it is shirk (polytheism) that expels one from the fold of Islam. The belief that surahs have servants (khuddam) is among the beliefs of sorcerers and has no basis in Islamic law. It is one of the satanic lies and superstitions that have no support in the Quran or Sunnah.