Add identity endpoint

backend/spec/api.md

@@ -40,6 +40,14 @@ Notes:
 - Return `data` is a single plan struct matching `id`
 - If plan does not exist, return `404` with `code=not-found`
 
+--- Identity routes
+
+## `async fn get_identity(...) -> Response`
+
+- Serves `GET /identity`
+- Authorizes anyone, but must be authorized
+- Return `data` is an `Identity` struct
+
 --- Tenant routes
 
 ## `async fn list_tenants(...) -> Response`

backend/spec/models.md

@@ -3,6 +3,14 @@ This file describes the domain model. This description should be translated into
 - Fields marked as private should use `#[serde(skip_serializing)]` in their definition.
 - Fields marked as readonly should use `#[serde(skip_deserializing)]` in their definition.
 
+# Identity
+
+Identity is a description of a user.
+
+- `pubkey` - the user's nostr pubkey
+- `is_admin` - whether the user is an admin
+- `is_tenant` - whether the user has an account
+
 # Activity
 
 Activity is an audit log of all actions performed by a user or a worker process. This allows us to trace history to create invoices, synchronize actions to external services, and debug system behavior.