Changelog

Market data

• Added GET /api/v5/market/history-mark-price-candles for historical mark price candlesticks, complementing the existing index and trade-price candle endpoints.
• The order book endpoint GET /api/v5/market/books now accepts a sz value up to 400 for spot and margin instruments (previously 400 was restricted to specific instrument types).
• New WebSocket channel mark-price-candle{bar} delivers mark price candles in real time, matching the request-cadence of index-candle{bar}.