List entity charts

Returns every entity chart with the headline state of its current edition: the edition date, whether narratives have been written yet, and what sits at rank 1. Each chart's source says whether its entries measure entity mentions or guest appearances, group tabs the directory into overall, entertainment, and sports, and windows lists the windows that chart publishes. Use the returned category_slug to fetch a full chart. Every chart lists, but leader is omitted for charts the caller may not read: an API key reads every chart, while a session without paid Radar access reads only the all chart.