v1.0.0-beta.27

Major Changes

• f05af49: Replace market websocket subscribe/unsubscribe methods with per-consumer subscription leases. Use client.market.acquireL1BookSubscription() and client.market.acquireFundingRateSubscription() to obtain a MarketSubscriptionLease, await lease.ready for the first snapshot, and call lease.close() to release only that consumer. L1 book and funding rate streams now ref-count active leases independently and only close the underlying websocket stream after the final lease is closed.