I want to build a scorecard rule that restricts available choices like an enum. For example, ensure that I have a component type defined that can only be one of "service", "application", "tool" or "documentation" but nothing else.

These operators are already available in the search endpoints: https://docs.port.io/search-and-query/comparison-operators#in and https://docs.port.io/search-and-query/comparison-operators#notin