Generate Prefix-Based Product Suggestions

## Problem Given distinct lowercase product names and a lowercase search word, return suggestions after each typed character. For every non-empty prefix, return up to three lexicographically smallest products that start with that prefix. ### Function Contract Implement `suggested_products(products, search_word) -> list[list[str]]`. ### Constraints - `1 <= len(products) <= 50000` and each product length is between 1 and 100. - `1 <= len(search_word) <= 100`. - All strings contain only lowercase English letters. - Products are distinct; the input order does not determine suggestion order. ### Examples - Products `["mobile","mouse","moneypot","monitor","mousepad"]` and search word `"mouse"` produce the standard prefix lists beginning with `["mobile","moneypot","monitor"]` for `m` and `mo`. - Once a prefix has no matches, that and all longer prefix lists are empty. ```hint Limit work per trie node If using a trie, each node needs only its three smallest suggestions, not every product below it. ``` ```hint Sorted ranges also work After sorting products, maintain the lower and upper indices whose strings still match the current prefix. ``` ### Edge Cases - Fewer than three matches are returned without padding. - A product equal to the current prefix is a valid suggestion. - The first character may have no matching product.