Returns paginated historical headlines for the Global Macro Sentiment Indices (GMSI) dataset for a given country and topic over a date range (up to 90 days), including per-headline directional and semantic sentiment scores. Use match_type to filter by domestic or international coverage, or return both with COMBINED. Pass the next_token from each response into the next request to page through results. Get valid country codes from GET /countries (browse all) or GET /countries/search (search by name). Get valid topics from GET /headlines/topics/gmsi.