Resolve a (possibly relative) reference URI against a base model URI, so an
IfcExternalReference.Location like ../shared/grid.ifc becomes an absolute
model URI addressable in the registry. Absolute references (with a scheme,
or protocol-relative) pass through unchanged.
Uses the standard URL resolver when the base is absolute; falls back to a
plain path join when the base has no scheme (e.g. a bare filename in tests).
Resolve a (possibly relative) reference URI against a base model URI, so an
IfcExternalReference.Locationlike../shared/grid.ifcbecomes an absolute model URI addressable in the registry. Absolute references (with a scheme, or protocol-relative) pass through unchanged.Uses the standard URL resolver when the base is absolute; falls back to a plain path join when the base has no scheme (e.g. a bare filename in tests).