Function jit_control_map 

pub extern "C" fn jit_control_map(_ctx: *mut JITContext) -> u64

map(array, fn) - transform each element

SURFACE (W10 jit-playbook §5 / ADR-006 §2.7.4): same JitArray deletion as jit_control_fold plus the result allocation goes through the deleted JitArray::from_vec(...).heap_box(). Kinded rebuild allocates a TypedArray<T> for the inferred element kind.