feat(FN-003): add tool manifest registry with FastAPI CRUD and built-in manifests

- Add ToolManifest Pydantic models with validators for ports, mounts, health checks, and traefik config

- Implement in-memory ToolRegistry with YAML loading and built-in manifest scanning

- Add FastAPI CRUD routes for listing, retrieving, and creating tool manifests

- Include built-in manifests for runfusion and code-server

- Harden web Dockerfile with unprivileged nginx and port 8080

- Add tool manifest specification documentation and architecture updates

Fusion-Task-Id: FN-003

apps/api/app/config.py

@@ -20,6 +20,9 @@ class Settings(BaseSettings):
     # Database
     database_url: str = "postgresql://postgres:postgres@localhost:5432/headquarter"
 
+    # CORS
+    cors_origins: str = "http://localhost:5173"
+
     # Deployment
     root_domain: str = "localhost"
     tool_subdomain_pattern: str = "{tool}-{project}-{user}.tools.{root_domain}"