Fixes for automatic chat retries, panel completion reporting, and conversation duration

Sensei, our AI conversation quality coach, found these problems by reviewing completed conversations and production signals.

• Fixed cases where the automatic retry after a connection error never ran in participant text conversations, Design chat, and Analysis chat.
• Fixed cases where a completed panel interview ended with a thank-you message but skipped reporting completion to Prodege or Cint.

New text conversations now include time on the welcome screen in their displayed duration, fixing cases where a one-answer conversation showed 0 sec.