fix: setup complete_setup should verify company and agent exist #587
Description
Summary
The POST /api/v1/setup/complete endpoint currently only checks that at least one provider is configured before marking setup as complete. It should also verify that a company and at least one agent have been created.
Current behavior
Only checks app_state.provider_registry length > 0.
Expected behavior
Also check:
- Company name is set (via settings or a company service)
- At least one agent exists (via settings "company.agents" key)
Context
Found during PR #584 review. Deferred because it may need new service methods or settings queries.