App Composition Rules

app/ is the composition root for runtime wiring.
Create registries, stores, command sets, input adapters, and renderer/view adapters here.
Do not implement domain rules, command behavior, rendering backend logic, or React UI here.
App composition may import from all layers, but lower layers must not import from app/.
Keep factories testable; avoid module-level mutable singleton state unless explicitly required by the runtime entrypoint.