v0.7.2

What's New

New Order API

• RithmicOrder struct + place_order() method on RithmicOrderPlantHandle — supports trigger prices and trailing stops
• TrailingStop configuration struct for trailing stop orders

Ticker Plant Unsubscribe

• unsubscribe(symbol, exchange) — unsubscribe from market data
• unsubscribe_order_book(symbol, exchange) — unsubscribe from order book depth-by-order updates

Serde-Compatible Order Types

• OrderSide, OrderType, TimeInForce enums with optional serde support and flexible FromStr parsing
• OrderStatus::Expired variant added

Docs & Examples

• Recommended default connection strategy changed from Simple to Retry
• Reconnect example simplified (no more manual sleep/retry)
• All contract symbols updated to ESH6
• README updated with new RithmicOrder API examples

Deprecated

• place_new_order() — use place_order(RithmicOrder) instead

See CHANGELOG.md for full details.