Add sync_ai_operator_config_from_code() which overwrites the DB-cached ai_operator_settings row from ai_operator_default_config() on startup of ai_orchestrator_service and ai_voice_runtime_service. Greeting and system prompt changes now go through git + deploy instead of manual psql/API edits to prod. Also adds a root README pointing to existing docs. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>