Spirit Airlines said in court papers filed Monday that it was forced to ground its fleet for good over the weekend because "recent geopolitical events resulted in a massive and sustained increase in fuel prices." While the court papers did not specify the nature of those geopolitical events, jet fuel prices have soared in the two months since the start of the war in Iran . "The Debtors and their advisors searched for increased capital and any sources of savings or liquidity, leaving no option unexplored," the airline stated in records filed Monday in federal bankruptcy court in the Southern District of New York. "It became clear on Thursday that sufficient incremental liquidity would not be found, and that there were no longer any viable paths to a restructuring or continued operations." But Spirit waited until early Saturday to pull the plug on its operations , stranding thousands of travelers midtrip and forcing countless others to rebook on other airlines.…