The generated schema previously used `as const` on entire model/enum/typeDef
objects, causing TypeScript to deeply infer literal types for all nested
properties. This is unnecessary for `attributes`, `default`, and `foreignKeyFor`
which are only used at runtime, not in CRUD type computations.
Changes:
- Add type assertions (`as readonly AttributeApplication[]`, `as FieldDefault`,
`as readonly string[]`) to prevent deep const inference on these properties
- Extract `FieldDefault` type alias from `FieldDef` for cleaner generated code
- Change `FieldHasDefault` to use key existence check (`'default' extends keyof`)
instead of value type check, enabling the `default` widening
- Conditionally import `AttributeApplication` and `FieldDefault` only when used
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
