Multi-tenant backend state API for Ito projects.
ito-backend is a Layer 3 adapter that exposes Ito project state
(changes, tasks, modules) via a RESTful HTTP API. It delegates all business
logic to [ito_core] and communicates exclusively in JSON.
All project-scoped routes are nested under /api/v1/projects/{org}/{repo}/.
Authentication uses admin tokens and HMAC-SHA256 derived per-project tokens.
An organization/repository allowlist is enforced before token validation.
The public surface is intentionally minimal: call [serve] with a
[BackendServerConfig] to
start the server.