Explain 'Branded Types' for Domain-Driven Design (DDD).

Branded types (or 'Flavoring') allow you to distinguish between identical primitive types at the type level to enforce domain rules.

In DDD, a UserId and an AccountId shouldn't be interchangeable just because they are both strings. TypeScript's structural typing would normally allow this. Branding involves intersecting a primitive type with a unique 'tag' object. This forces the developer to explicitly cast or validate a string before it can be used as a specific domain ID, preventing logic bugs where the wrong ID is passed to a service.