/history/{session_id} now returns a 'name' field alongside messages.
resumeSession() uses data.name first, then the sessionNames map, then
raw ID as fallback — so named sessions display correctly even on page
load before the sessions panel has been opened.
'Resumed session X' message also now shows the friendly name.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>