Discover companies by several criteria

Multi-criteria discovery over the same published companies the directory lists: free text, industry, HQ country, data residency region, deployment model, product name, whether Trooth holds a witnessed reading, and profile changes since a date. A company is matched only by facts its public page shows: residency and deployment are searchable only while the company shows the section that renders them. Filters are exact, case-insensitive matches on what the company published; a company that published nothing for a filtered field is absent from the answer, which is not a no. Order is the directory's: witnessed first, then the most recent reading, then name; never by a figure. Each result carries facts, whole days counted from timestamps on the record (days_since_last_witnessed, days_since_profile_updated), which rate nothing. Cursor pagination only; a cursor is bound to the filters it was issued with. An unknown filter is refused. Errors are always RFC 9457 problem details (codes at /api/problems). Cached at the edge for 60 seconds with a 300 second stale-while-revalidate window. Readable cross-origin: the response carries Access-Control-Allow-Origin: * and never Access-Control-Allow-Credentials, so a browser on any site may read it without cookies.