Iterate over array elements
The For Each step takes an array from an upstream step and iterates over its elements, executing a set of body steps once per element in parallel. It's the entry point of a loop pattern that always ends with a Collect step.
The step reads the first array field from its input record and creates N parallel iterations, one for each element. The item output (slot 1) represents a single element from the array. All steps between For Each and its paired Collect step are the "loop body" and execute once per iteration. If the array is empty, For Each skips the body entirely and advances past the Collect step. The onIterationFailure config controls whether a failed iteration fails the entire run (FAIL) or is skipped (SKIP, the default).