Decorators that provide value validation don't do it when defined on properties

```tsp
model Foo {
@maxLength(3)
foo: string;
}

@maxLength(3)
scalar Bar extends string;

const bar: Bar = "abcdef"; // validate

const foo: Foo = #{ foo: "abcde" }; // does not

```
[Playground Link](https://typespec.io/playground/?c=bW9kZWwgRm9vIHsKICBAbWF4TGVuZ3RoKDMpCiAgZm9vOiBzdHJpbmc7Cn0KCs4gc2NhbGFyIEJhciBleHRlbmRzySxjb25zdMY%2FxFw9ICN7xg4iYWJjZGUiIH07IC8vIGRvZXMgbm90xzBiYXI6xU89xyhmIsUndmFsaWRhdGUK&e=%40typespec%2Fopenapi3&options=%7B%7D)