feat: 初始化考培练系统项目

- 从服务器拉取完整代码
- 按框架规范整理项目结构
- 配置 Drone CI 测试环境部署
- 包含后端(FastAPI)、前端(Vue3)、管理端

技术栈: Vue3 + TypeScript + FastAPI + MySQL

backend/app/models/position.py

@@ -0,0 +1,54 @@
+"""
+岗位（Position）数据模型
+"""
+
+from typing import Optional
+from sqlalchemy import String, Integer, Text, ForeignKey, Boolean, JSON
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+from typing import Optional, List
+
+from .base import BaseModel, SoftDeleteMixin, AuditMixin
+
+
+class Position(BaseModel, SoftDeleteMixin, AuditMixin):
+    """
+    岗位表
+
+    字段说明：
+    - name: 岗位名称
+    - code: 岗位编码（唯一），用于稳定引用
+    - description: 岗位描述
+    - parent_id: 上级岗位ID，支持树形结构
+    - status: 状态（active/inactive）
+    """
+
+    __tablename__ = "positions"
+    __allow_unmapped__ = True
+
+    name: Mapped[str] = mapped_column(String(100), nullable=False, index=True)
+    code: Mapped[str] = mapped_column(String(100), nullable=False, unique=True, index=True)
+    description: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
+
+    parent_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("positions.id", ondelete="SET NULL"))
+    status: Mapped[str] = mapped_column(String(20), default="active", nullable=False)
+    
+    # 新增字段
+    skills: Mapped[Optional[List]] = mapped_column(JSON, nullable=True, comment="核心技能")
+    level: Mapped[Optional[str]] = mapped_column(String(20), nullable=True, comment="岗位等级")
+    sort_order: Mapped[Optional[int]] = mapped_column(Integer, default=0, nullable=True, comment="排序")
+
+    # 关系
+    parent: Mapped[Optional["Position"]] = relationship(
+        "Position", remote_side="Position.id", backref="children", lazy="selectin"
+    )
+    
+    # 成员关系（通过关联表）
+    members = relationship("PositionMember", back_populates="position", cascade="all, delete-orphan")
+    
+    # 课程关系（通过关联表）
+    courses = relationship("PositionCourse", back_populates="position", cascade="all, delete-orphan")
+
+    def __repr__(self) -> str:
+        return f"<Position(id={self.id}, name={self.name}, code={self.code}, status={self.status})>"
+
+