angular-typechecker

Implementation blueprint from spike experiments. Requirements, proven patterns, and verified knowledge for building angular-typechecker -- the v0.1.2 Storybook input-set-membership boundary (Phase 16 gate = GO, branch 4a), the shipped v0.1.0 reference-walk engine, Vite/Analog Storybook query-import guidance (the `vite/client` recipe + optional advisory), and the v0.2.1 Angular CLI builder GATE A' (Phase 21 = GO: the CJS->ESM `await import()` bridge survives `convertNxExecutor` + a real `ng run`). Auto-loaded during implementation work.