ADM-OPERATOR-USER-202 - Update Authenticated Operator User

PUT https://example.com/v1/operator-users

Overview
Updates the authenticated operator user profile (the operator user associated with the provided credentials).

User scoping
Admin endpoint. Only operator users can call this endpoint (dj-client: OPERATOR). The updated user is the authenticated operator user.

Store scoping
dj-store and dj-store-view define the request context. The authenticated operator user can be restricted to specific stores using stores.

Validation rules
If stores is provided, it must be an array of store external identifiers (externalId); duplicates are ignored.

Business rules
Replacement rules for stores:
- If omitted: the current store restriction is preserved.
- If provided as an empty array: removes any restriction (allowed on all stores).
- If provided with values: replaces the current restriction.

Errors
Returns validation errors (400), authentication errors (401), authorization errors (403), and unexpected server errors (500).