Comprehensive 4-phase plan: (1) Fix golden tests to use preprocessor [1hr quick win], (2) Add enum preprocessor for sum types [4-6hrs], (3) Activate Result plugin pipeline with Transform/declarations [6-8hrs], (4) Integration testing and polish [2-3hrs]. Total: 13-18 hours. Delivers end-to-end Result<T,E> with Ok()/Err() constructors, enum support, and full .dingo → .go → run workflow.
