Implement a basic algorithm to parse and filter a stream of incoming data efficiently for an Equativ pipeline.
Implement parse_and_filter(stream, allowed_categories, min_value). Each stream item is a pipe-delimited string in the format record_id|category|value; ignore malformed records and invalid integer values. Return parsed records whose category is allowed and whose value is at least min_value, preserving input order.
def parse_and_filter(stream, allowed_categories, min_value):