Contract for walker stop signal events.
Emitted when Walker.stop() is called to interrupt a running walker. Contains metadata about which walker and strategy should be stopped.
Supports multiple walkers running on the same symbol simultaneously by including walkerName for filtering.
symbol: string
symbol - Trading symbol (e.g., "BTCUSDT")
strategyName: string
strategyName - Name of the strategy to stop
walkerName: string
walkerName - Name of the walker to stop (for filtering)