bc8f1c353f
Phone-number logins return id_profile=null, mobile_number="177******08", and
email="" (empty string, not null). The previous fallback used `??`, which only
short-circuits on null/undefined, so an empty email string clobbered the
mobile_number fallback and the displayName ended up null — leaving the
DeepSeek card stuck on the "${label} 会话" placeholder.
Switch to a truthy pickString helper that requires a non-empty trimmed string
before accepting a candidate, and prefer mobile_number over email so the
masked phone number shows up exactly the way DeepSeek's own sidebar renders it.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>