libraryUri property
This field is omitted if getSuggestions was used rather than getSuggestions2.
This field is omitted if this suggestion corresponds to a locally declared element.
If this suggestion corresponds to an already imported element, then this field is the URI of a library that provides this element, not the URI of the library where the element is declared.
If this suggestion corresponds to an element from a not yet imported library, this field is the URI of a library that could be imported to make this suggestion accessible in the file where completion was requested, such as package:foo/bar.dart or file:///home/me/workspace/foo/test/bar_test.dart.
Implementation
String? libraryUri;