Whether a basemap definition carries something to draw: a url, a non-empty tiles list, a
style, type: "maplibre", or one of the types configured by their own block — image,
hillshade, wmts, wms. The block itself is not inspected here: its absence is the type's
own reader's to report.
Parameters
definition: unknown
A basemap entry, as the profile or a caller wrote it.
Whether a basemap definition carries something to draw: a
url, a non-emptytileslist, astyle,type: "maplibre", or one of the types configured by their own block —image,hillshade,wmts,wms. The block itself is not inspected here: its absence is the type's own reader's to report.