feat: TenantRuntime/Registry——每租户懒建 engine(WAL/pool2)+文件加载器+站点解析

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

app/engine/models.py

@@ -2,7 +2,7 @@ import enum
 import uuid
 from datetime import datetime, timezone
 
-from sqlalchemy import String, Text, Boolean, Integer, ForeignKey, JSON, Enum as SAEnum
+from sqlalchemy import String, Text, Boolean, Integer, ForeignKey, JSON, Enum as SAEnum, text
 from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, relationship
 
 
@@ -159,3 +159,27 @@ class LeadPushLog(Base):
         default=lambda: datetime.now(timezone.utc),
         onupdate=lambda: datetime.now(timezone.utc),
     )
+
+
+async def ensure_schema(engine) -> None:
+    """create_all + 旧库加列迁移(自 app/main.py lifespan/_migrate 提取,逻辑逐字等价)。
+
+    jc 上线库(conversations 无 page_token / evaluations 无 correction_count)
+    经此升级;新库 create_all 已含全部列,加列分支空跑。TenantRegistry 懒建
+    每租户库时复用(Phase 1);生产装配见 app/main.py lifespan。
+    """
+    async with engine.begin() as conn:
+        await conn.run_sync(Base.metadata.create_all)
+        result = await conn.execute(text("PRAGMA table_info(conversations)"))
+        columns = {row[1] for row in result}
+        if "page_token" not in columns:
+            await conn.execute(text(
+                "ALTER TABLE conversations ADD COLUMN page_token VARCHAR(64)"
+            ))
+
+        result = await conn.execute(text("PRAGMA table_info(evaluations)"))
+        columns = {row[1] for row in result}
+        if "correction_count" not in columns:
+            await conn.execute(text(
+                "ALTER TABLE evaluations ADD COLUMN correction_count INTEGER DEFAULT 0"
+            ))