```

refactor(core,ai): 调整模块导入路径并移除废弃文件

- 修复 scheduler.py 中的导入路径错误，将 reports.service
  改为 reports.services
- 移除废弃的 app/core/background/task_queue.py 文件
- 移除废弃的 app/modules/ai_agent/adapters.py 文件
- 修复 ai_memory/service.py 中的导入路径错误，将
  events.service 改为 events.services
```

app/modules/business/models/suppliers.py

@@ -0,0 +1,30 @@
+from decimal import Decimal
+
+from sqlalchemy import Integer, Numeric, String
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.database import Base
+from app.modules.business.constants import (
+    RiskLevel,
+    StatusValue,
+)
+from app.modules.business.models.common import TimestampMixin
+
+
+class Supplier(Base, TimestampMixin):
+    __tablename__ = "suppliers"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    code: Mapped[str] = mapped_column(String(64), unique=True, index=True)
+    name: Mapped[str] = mapped_column(String(255), index=True)
+    category: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
+    contact: Mapped[str | None] = mapped_column(String(128), nullable=True)
+    quality_score: Mapped[Decimal] = mapped_column(Numeric(5, 2), default=0)
+    delivery_score: Mapped[Decimal] = mapped_column(Numeric(5, 2), default=0)
+    price_score: Mapped[Decimal] = mapped_column(Numeric(5, 2), default=0)
+    risk_level: Mapped[str] = mapped_column(String(32), default=RiskLevel.LOW, index=True)
+    blacklist_status: Mapped[str] = mapped_column(
+        String(32),
+        default=StatusValue.NORMAL,
+        index=True,
+    )