Manage Elementor form submissions in bulk (1-50 operations). Actions: "mark_read" and "mark_unread" toggle the read state; "trash" moves a submission to trash and "restore" brings it back from trash (both reversible); "update_values" overwrites submitted field values (requires "values", an object of field_id to new value; only fields the submission already has can be changed). update_values cannot be undone, so the result returns "previous_values" for the changed fields: keep them to revert if needed. Permanent deletion is not supported. Per-operation results are returned in order, each with its submission_id; the top-level status is ok, partial_error or error. Trash and restore results include "in_trash".