"""§7 B 阶段:Storage 落 PG。

入口:
    from core.storage import get_engine, session_scope, ensure_local_sentinel
    from core.storage.models import User, Task, Message, Run, UsageEvent

ZCBOT_DB_URL 环境变量必填(本地连测试 / staging PG;SaaS 连生产 PG)。
未设置时 get_engine() 抛 RuntimeError 并指引设置。
"""
from .engine import (
    SENTINEL_USER_ID,
    ensure_local_sentinel,
    get_engine,
    session_scope,
)

__all__ = [
    "SENTINEL_USER_ID",
    "ensure_local_sentinel",
    "get_engine",
    "session_scope",
]