Tests that embedded enums are registered in the app schema but don’t create
their own database tables (they’re inlined into parent models as a single column).
Tests filtering records by embedded enum variant.
Validates that enum fields can be used in WHERE clauses (comparing discriminants),
and verifies the driver-level representation: the predicate compares the status
column to an I64 discriminant, not a string or other type. On SQL the predicate
is emitted as column = $0 with an I64 param; on DynamoDB it lowers to a
Scan whose filter inlines the I64 value directly.