Policy Alias Match Monitor

A policy scanner searches an incident feed for a short template. A template character can match the same character in the feed, or it can match one of its approved replacement characters. Each mapping describes one allowed replacement from a template character to a feed character. Replacements are checked per character position. The template must match one contiguous substring of the feed. Input Format: You are given strings source and pattern, and an array mappings where each mapping is [from, to]. Output Format: Return true if pattern can match any contiguous substring of source using the allowed replacements, otherwise return false.