Review add/remove curves & dap within `BECWaveformWidget`
If you try to call set_x(samy) if a DAP process was added for samx, then there is a popup error currently and the DAP curve is removed. It is desirable to handle this error more gracefully for the user. In addition, the color palette of curves for scan_segments and dap should not default to the identical color palette, but should share the palette