The generic bound only, never surfaced to a consumer's inferred type --
the same variance workaround env-cap's EnvSchema uses so TFields extends FieldsShape still infers a precise, per-key literal type from the actual
object literal passed to buildData.
The generic bound only, never surfaced to a consumer's inferred type -- the same variance workaround env-cap's
EnvSchemauses soTFields extends FieldsShapestill infers a precise, per-key literal type from the actual object literal passed tobuildData.