```

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/projects.py

@@ -0,0 +1,51 @@
+from datetime import date, datetime
+from decimal import Decimal
+
+from sqlalchemy import Date, DateTime, Integer, Numeric, String, Text
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.database import Base
+from app.modules.business.constants import (
+    PriorityValue,
+    RiskLevel,
+    SourceSystem,
+    StatusValue,
+)
+from app.modules.business.models.common import TimestampMixin
+
+
+class Project(Base, TimestampMixin):
+    __tablename__ = "projects"
+
+    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)
+    owner: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
+    status: Mapped[str] = mapped_column(String(64), default=StatusValue.INITIATED, index=True)
+    priority: Mapped[str] = mapped_column(String(32), default=PriorityValue.P2)
+    progress_percent: Mapped[int] = mapped_column(Integer, default=0)
+    risk_level: Mapped[str] = mapped_column(String(32), default=RiskLevel.LOW, index=True)
+    budget_amount: Mapped[Decimal] = mapped_column(Numeric(14, 2), default=0)
+    actual_amount: Mapped[Decimal] = mapped_column(Numeric(14, 2), default=0)
+    start_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    due_date: Mapped[date | None] = mapped_column(Date, nullable=True, index=True)
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    source_system: Mapped[str] = mapped_column(String(64), default=SourceSystem.INTERNAL)
+    external_id: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
+
+class WorkTask(Base, TimestampMixin):
+    __tablename__ = "work_tasks"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    code: Mapped[str] = mapped_column(String(64), unique=True, index=True)
+    title: Mapped[str] = mapped_column(String(255), index=True)
+    project_code: Mapped[str | None] = mapped_column(String(64), nullable=True, index=True)
+    owner: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)
+    status: Mapped[str] = mapped_column(String(64), default=StatusValue.TODO, index=True)
+    priority: Mapped[str] = mapped_column(String(32), default=PriorityValue.P2)
+    due_date: Mapped[date | None] = mapped_column(Date, nullable=True, index=True)
+    completed_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)
+    blocker: Mapped[str | None] = mapped_column(Text, nullable=True)
+    description: Mapped[str | None] = mapped_column(Text, nullable=True)
+    source_system: Mapped[str] = mapped_column(String(64), default=SourceSystem.INTERNAL)
+    external_id: Mapped[str | None] = mapped_column(String(128), nullable=True, index=True)