Catalogue and market lifecycle

Events group markets. Each market is a binary contract with YES and NO sides.

1. Open the /events stream and buffer incoming frames.
2. Call GET /events, following its cursor until it is null. Each event contains its markets. GET /markets and the individual event and market endpoints can be used for targeted reads.
3. Apply buffered lifecycle frames, then process the stream live.

Use status_revision to order updates to a market. Apply market.status_changed, market.details_changed, market.settled, and market.voided only when their status_revision is greater than the revision already stored. A market.details_changed can arrive after a market has closed and before its settlement events.

An open event can gain a market: it arrives as market.created and comes before every market.status_changed of that market. Apply it only to a market not stored yet.

Regular broker orders are accepted only while a market is active. A suspended market rejects new orders and amends but still allows cancels. A closed, settled, or voided market accepts no new trading commands. Markets belonging to one event are independent: one market can close, settle, or be voided while the other markets continue trading.

Use the repeatable lang query parameter when only selected locales are needed. Without it, all available locales are returned.