feat: 添加文档管理系统前后端基础功能

- 新增后端FastAPI应用，包含用户管理、文档管理和操作日志功能
- 实现JWT认证机制，支持用户注册、登录、登出操作
- 添加数据库模型定义，包括用户表、文档表和操作日志表
- 实现文档的增删改查功能及权限控制
- 添加管理员功能，支持用户管理和全局操作日志查看
- 新增前端界面，实现完整的用户交互体验
- 配置环境变量示例和Git忽略规则
- 编写详细的README文档，包含安装和使用说明

schemas.py

@@ -0,0 +1,110 @@
+from sqlalchemy.orm import Session
+from pydantic import BaseModel, validator, EmailStr
+from typing import Optional
+from datetime import datetime
+import re
+
+
+class UserBase(BaseModel):
+    username: str
+    email: Optional[EmailStr] = None
+    full_name: Optional[str] = None
+
+
+class UserCreate(UserBase):
+    password: str
+    is_admin: bool = False  # 新增管理员字段，默认为False
+    
+    @validator('username')
+    def username_alphanumeric(cls, v):
+        if not v.replace('_', '').isalnum():
+            raise ValueError('用户名只能包含字母、数字和下划线')
+        if len(v) < 3 or len(v) > 20:
+            raise ValueError('用户名长度必须在3-20个字符之间')
+        return v
+    
+    @validator('password')
+    def password_strength(cls, v):
+        if len(v) < 6:
+            raise ValueError('密码长度至少6位')
+        return v
+
+
+class UserLogin(BaseModel):
+    username: str
+    password: str
+
+
+class UserUpdate(BaseModel):
+    email: Optional[EmailStr] = None
+    full_name: Optional[str] = None
+    password: Optional[str] = None
+    
+    @validator('password')
+    def password_strength(cls, v):
+        if v and len(v) < 6:
+            raise ValueError('密码长度至少6位')
+        return v
+
+
+class UserResponse(UserBase):
+    id: int
+    is_admin: bool  # 添加管理员标识
+    is_active: bool
+    created_at: datetime
+    updated_at: Optional[datetime] = None
+    
+    class Config:
+        orm_mode = True
+
+
+# 文档相关模式
+class DocumentBase(BaseModel):
+    title: str
+    content: Optional[str] = None
+    description: Optional[str] = None
+    file_type: str = "txt"
+    file_size: int = 0
+    is_public: bool = False
+
+class DocumentCreate(DocumentBase):
+    pass
+
+class DocumentUpdate(BaseModel):
+    title: Optional[str] = None
+    content: Optional[str] = None
+    description: Optional[str] = None
+    file_type: Optional[str] = None
+    is_public: Optional[bool] = None
+
+class DocumentResponse(DocumentBase):
+    id: int
+    owner_id: int
+    created_at: datetime
+    updated_at: Optional[datetime] = None
+    
+    class Config:
+        orm_mode = True
+
+# 操作日志相关模式
+class UserOperationLogBase(BaseModel):
+    operation: str
+    details: Optional[str] = None
+    ip_address: Optional[str] = None
+    user_agent: Optional[str] = None
+
+class UserOperationLogResponse(UserOperationLogBase):
+    id: int
+    user_id: int
+    created_at: datetime
+    
+    class Config:
+        orm_mode = True
+
+# Token响应模式
+class Token(BaseModel):
+    access_token: str
+    token_type: str
+
+class TokenData(BaseModel):
+    username: Optional[str] = None