Store the person uuid the master issues, so renames keep our identity

The welcome now carries a personId; it lands in the instance_id setting
and rides on every hello and HTTP report from then on. The master keys
the person by that uuid, so changing instance_name moves our history to
the new name instead of starting a stranger. Read-only in Settings on
purpose — editing it by hand would detach this machine from its person.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/db.ts

@@ -155,6 +155,10 @@ seedSetting.run('max_concurrent_accounts', '5');
 seedSetting.run('tick_interval_seconds', '60');
 seedSetting.run('master_dashboard_url', 'https://master.juicerroom.com');
 seedSetting.run('instance_name', '');
+// The person uuid the master issues in its welcome. Stored, then presented on
+// every hello/report — it is what lets a renamed instance_name stay the same
+// person on the master. Never edited by hand.
+seedSetting.run('instance_id', '');
 seedSetting.run('trading_hours', 'full_cme');
 // Solves the captchas the AutoBuyer runs into. Blank uses the key hardcoded in
 // app/api/autobuyer/captcha; set this (or TWOCAPTCHA_API_KEY) to bill another