Adds DEMO_BOT_PERSONA env var (inline JSON or file:<path>) so
self-hosted instances can replace Bruno-in-Berlin with their own
demo account identity and content pools. No-op for trails.cool — the
built-in Bruno persona remains the default.
- DemoPersona type + Zod schema validation
- loadPersona() cached at boot; falls back to default on any failure
- ensureDemoUser throws DemoPersonaUsernameClashError when the
persona username is already a real user; server declines to
schedule demo jobs for that process
- isDemoUser flag moved from hardcoded "bruno" check to loader-supplied
boolean computed from the running persona
- docs/demo-persona.md explains the schema + operator flow
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
