Incorrect roughness used for widening banks
When generating a channel with widening using the BASEchange CLI, the widened section is supposed to use the roughness of the rest of the channel for its banks by default, with a switch (#59 (closed)) allowing customisation of this value.
Instead, the widened banks currently default to the widened section's bed roughness.
This is likely specific to the widened trapezoidal channel factory and does not affect the file input roughness.