Release v0.2.1

Changes

Added

• Add automatic WebsocketManager reconnect attempts with bounded exponential backoff after disconnects or transport errors.
• Replay active WebSocket subscriptions after reconnect so Info::subscribe() callbacks resume without manual re-subscription.

Fixed

• Keep WebSocket subscription replay lock-free and synchronized with unsubscribe by tracking per-identifier subscription state, in-flight subscribe/replay sends, and final unsubscribe phases with atomics.
• Avoid stale server-side subscriptions when a reconnect replay overlaps with the last local unsubscribe() for a channel.
• Coalesce multiple callbacks on the same channel into one wire subscription until the last callback unsubscribes.

Tests

• Add offline SubscriptionTracking tests covering subscribe while disconnected, callback routing after unsubscribe, concurrent subscribe/unsubscribe, wire subscription coalescing, and unsubscribe-before-resubscribe ordering using a local in-process WebSocket server.