package:source_helper v1.4.0

• Require analyzer: '>=10.1.0 <15.0.0' and source_gen: ^4.1.2.
• Add DartType.toStringNonNullable() and DartType.enumConstants to
  DartTypeExtension.
• Add class-model helpers shared by code generators:
  • createSortedFieldSet, InheritedMemberScope, fieldOverrideChain and
    firstAnnotationOnProperty for the field set of a class and its
    supertypes.
  • constructorByName, planConstruction with ConstructorPlan, and
    typeParameterListCode for constructor invocations.
  • ExecutableElementExtension.qualifiedName for invocation targets.