Returns global news coverage and sentiment for any company, stock ticker, or topic. Primary source: GDELT Project v2 (250M+ articles, ML tone scoring). Fallback: Google News RSS with keyword heuristic. Returns article count, avg sentiment tone (−100 negative → +100 positive), top positive/negative headlines, and top news domains. Lookback: 1–30 days (default 3). Results cached 10 min.