Saving the actual wflow basins in staticgeoms

[hboisgon]

So far when building a wflow model we add a basins.geojson file in staticgeoms folder. This staticgeoms is however the basin delineation based on the hydrography_fn (merit_hydro) at its resolution and its basin IDs.

I think it would make more sense that basins.geojson would be directly the wflow subcatch delineation and IDs as in wflow_subcatch.map and maybe save a second shape for hydrography_fn (merit_hydro) shape and ID, for example basins_{hydrography_fn}.geojson or basins_high_resolution.geojson.

The current behavior is prone to error, as for example to clip a wflow model, IDs from wflow_subcatch map and not from merit_hydro should be used (the ones in basins.geojson). Also later if that file is used to compute basin statistics, this may lead to small errors.