Initial commit: KPI Management System Backend

Features:
- FastAPI backend with JWT authentication
- MySQL database with SQLAlchemy ORM
- KPI workflow: draft → pending → approved → evaluation → completed
- Ollama LLM API integration for AI features
- Gitea API integration for version control
- Complete API endpoints for KPI, dashboard, notifications

Tables: KPI_D_* prefix naming convention

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/models/notification.py

@@ -0,0 +1,58 @@
+"""
+通知 Model
+"""
+from datetime import datetime
+from typing import Optional, TYPE_CHECKING
+
+from sqlalchemy import String, Integer, Boolean, DateTime, Text, ForeignKey
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from app.core.database import Base
+
+if TYPE_CHECKING:
+    from app.models.employee import Employee
+    from app.models.kpi_sheet import KPISheet
+
+
+class Notification(Base):
+    """通知"""
+
+    __tablename__ = "KPI_D_notifications"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    recipient_id: Mapped[int] = mapped_column(ForeignKey("KPI_D_employees.id"), nullable=False)
+    type: Mapped[str] = mapped_column(String(50), nullable=False)
+    # kpi_submitted, kpi_approved, kpi_rejected, eval_reminder, etc.
+    title: Mapped[str] = mapped_column(String(200), nullable=False)
+    content: Mapped[Optional[str]] = mapped_column(Text)
+    related_sheet_id: Mapped[Optional[int]] = mapped_column(ForeignKey("KPI_D_sheets.id", ondelete="SET NULL"))
+    is_read: Mapped[bool] = mapped_column(Boolean, default=False)
+    read_at: Mapped[Optional[datetime]] = mapped_column(DateTime)
+    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)
+
+    # Relationships
+    recipient: Mapped["Employee"] = relationship("Employee", back_populates="notifications")
+    related_sheet: Mapped[Optional["KPISheet"]] = relationship("KPISheet")
+
+    def __repr__(self) -> str:
+        return f"<Notification id={self.id} type={self.type} recipient={self.recipient_id}>"
+
+
+class NotificationPreference(Base):
+    """通知偏好"""
+
+    __tablename__ = "KPI_D_notification_preferences"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    employee_id: Mapped[int] = mapped_column(ForeignKey("KPI_D_employees.id"), unique=True, nullable=False)
+    email_enabled: Mapped[bool] = mapped_column(Boolean, default=True)
+    in_app_enabled: Mapped[bool] = mapped_column(Boolean, default=True)
+    reminder_days_before: Mapped[int] = mapped_column(Integer, default=3)
+    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)
+    updated_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+    # Relationships
+    employee: Mapped["Employee"] = relationship("Employee")
+
+    def __repr__(self) -> str:
+        return f"<NotificationPreference employee={self.employee_id}>"