Returns paginated sentiment index aggregates for the Global Macro Sentiment Indices (GMSI) dataset for one or more countries and topics over a historical date range (up to 90 days), with one row per country per topic per timestamp (unlike GET /index/gmsi/historical/{country}, which is scoped to a single country and topic). Use country_preset and topic_preset to select a predefined grouping (e.g. G7, ECONOMIC DATA) or an individual country code / topic name. Use interval to switch between hourly and daily aggregation granularity. Use sentiment_type to switch between directional (topic-specific rules) and semantic sentiment models. Use index_type to filter by domestic or international headline coverage, or return both with COMBINED. Pass the next_token from each response into the next request to page through results. Get valid country presets from GET /headlines/topics/gmsi/countries/presets or individual codes from GET /countries. Get valid topic presets from GET /headlines/topics/gmsi/topics/presets or individual topics from GET /headlines/topics/gmsi.