Add lastLoginAt, lastLoginIp, lastLoginLocation to User schema. recordLogin() method called from all 5 login flows (phone, email, wx, password, register). Exposed in safeUser so info endpoint returns login metadata.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>