JSON Path Query on Map<String, Object> with Wildcard (*)

Given a JSON object represented as nested Map<String, Object> (no string parsing required), implement a jq-like path query. Input json: Map<String,Object> where values can be scalars or nested maps path: String dot-separated keys, may start with a leading dot Output Return the value at the path; if not found return null. Path rules Regular keys: .contacts.cell. Support wildcard * to match any key at the current level. .*.cell: iterate all top-level keys and continue searching for cell. If * is the last segment (e.g., contacts.*), return all key/value pairs under that object (e.g., as a Map). If wildcard produces multiple matches, return a collection (e.g., List<Object>). If there are no matches, return null. Example See Chinese section. Constraints Total nodes N <= 1e5 Path length K <= 100 Example Input json={fname:A, contacts:{cell:111, home:222}} path=.contacts.cell Output 111