Query features can be persisted as a view pipeline or a validator, and at the same time they can be FCV-gated (e.g. $toUUID since 8.0+, $sigmoid since 8.1+). The associated multiversion concerns (e.g. what if an user downgrades while a view using new query features exists?) are tested by view_definition_feature_compatibility_version.js and collection_validator_feature_compatibility_version.js.

Those tests need to be populated with new query features, but various branches currently have no test cases. This makes those tests are a no-op, and they regress on v8.0+ when test cases are added, due to SERVER-83754 but potentially also other changes.

We should add test cases and fix any related breakage.