### Description

This is a followup to #85926.

As part of the ingest processing pipeline, we call `CollectionUtils.ensureNoSelfReferences(...)` to ensure that a script processor didn't accidentally introduce a circular object. However, this check is only necessary if we know there was the potential for a circular option, which can only happen with either a custom processor (a plugin where we have no control), or a script processor. We should be able to only call this sanity check if we know we need it, rather than for every document.
server/src/main/java/org/elasticsearch/ingest/IngestDocument.java
} else if (context instanceof List<?> list) {
                try {
                    int index = Integer.parseInt(pathElement);
                    if (index < 0 || index >= list.size()) {
                        if (failOutOfRange) {
                            throw new IllegalArgumentException(
                                "["
                                    + index
                                    + "] is out of bounds for array with length ["
                                    + list.size()
                                    + "] as part of path ["
                                    + path
                                    + "]"
                            );
                        } else {
                            return false;
                        }
                    }
                    context = list.get(index);
                } catch (NumberFormatException e) {
                    return false;
                }
            } else {
                return false;
            }
        }
        String leafKey = fieldPath.pathElements[fieldPath.pathElements.length - 1];
        if (context instanceof Map<?, ?> map) {
            return map.containsKey(leafKey);
        }