State of `Differentiation` in Swift 6.4 updates

Hello everyone! Swift 6.4 released last week so it's time for another differentiable Swift update wrt the compiler! (See our previous update back in February here) What's new: Differentiation of throwing functions is finally supported on all platforms. Previously the work for throwing functions got cherry picked onto 6.3 release branches but wasn't picked up for Darwin platforms unfortunately. Work continues on autodiff-aware closure specialization. This will result in better optimized deriv...