Updated `AddSignatureAtAnnotation` to use `DetailBand` instead of `BottomMarginBand` for managing signature annotations. Adjusted logic to ensure signatures are placed in the detail section and only displayed on the specified page using the `BeforePrint` event. Reformatted constants for readability and updated `RemoveExistingSignatureById` to operate on `DetailBand`. Removed reliance on bottom margin height for positioning and introduced `annotation?.Y` for vertical placement.