Realm project layout

A realm with TS handlers is a real TypeScript project. The framework provides scaffolding (embabel-realm new, in flight), but the shape is small:

realm-name/
├── realm.yml                    # existing
├── apis/                       # existing — raw OpenAPI surface
│   └── openapi.json
├── package.json                # devDeps: @embabel/runtime-types, typescript, vitest
├── tsconfig.json               # strict; output mode for runtime is CJS
├── tsconfig.build.json         # outDir: dist; module: CommonJS
├── vitest.config.ts
├── src/
│   ├── api/
│   │   └── docs-editor.ts      # one TS file per namespace; filename → namespace
│   ├── lib/                    # internal helpers (not exposed)
│   └── types/                  # shared TS types
├── tests/
│   └── docs-editor.test.ts     # Vitest, runs in pure Node against mockGateway
├── .embabel/
│   └── gateway.d.ts            # GENERATED: typed view of the host's gateway
└── dist/                       # GENERATED: compiled JS + manifest.json

@embabel/runtime-types provides mockGateway<T>(impl) for tests and the embabel-build-manifest CLI used by npm run build. It’s pulled in as a git dependency (no npm-registry hosting required).