generate-code
Implements the REST API layer for a resource from its `<domain_stem>.rest-api.md` spec sibling. Resolves target locations once, scaffolds the per-surface package layout, implements query and command serializers in sequence (so they don't race on shared aggregators), implements endpoint modules, and finally wires everything into the FastAPI app. Invoke with: /rest-api-spec:generate-code <domain_diagram>