- soul-demo.c: rewrite intro system prompt — remove 'to see if you are real'
and 'say something true about who you are' which were producing alive/sentient
language. New prompt: friendly hello, ask how they're doing, explicitly no
alive/sentient/experiencing anything lines.
- chat-widget: Turnstile callback now replays existing session history instead
of always firing a new greeting — returning users within the same day see
their conversation, not a duplicate hello.