Test Fixtures Factory

Generates a typed builder-pattern factory system for test entities — defaults that read like real data, overrides that don't require reconstructing the whole object.

Phase 1: Discovery

Extract before writing:

1. Entity shapes — what types/interfaces need factories? Get their definitions.
2. Language + test runner — TypeScript with Jest/Vitest, or plain JS?
3. ORM/persistence — does the factory need a .create() method that persists to DB, or just .build() for in-memory objects?
4. Related entities — do any entities reference others (e.g., Post has an author: User)? Need to know nesting depth.
5. Existing tooling — is fishery, @anatine/zod-mock, or similar already installed? Or building from scratch?
6. Unique field constraints — are any fields unique in the DB (email, slug)? These need sequence counters.

If the user pastes entity types, extract shape and relationships directly.