Base sizing schema with common fields.
sizingName: string
Unique identifier for this sizing configuration
note: string
Optional developer note for documentation
maxPositionPercentage: number
Maximum position size as % of account (0-100)
minPositionSize: number
Minimum position size (absolute value)
maxPositionSize: number
Maximum position size (absolute value)
callbacks: Partial<ISizingCallbacks>
Optional lifecycle callbacks