feat: 完善前后端核心功能模块

后端:
- 新增认证(auth)、任务(tasks)、映射(mappings)、对账(reconciliation)、异常(exceptions)、导出(exports) API
- 新增核心模块: database, security, permissions, tenant, exceptions, error_handlers
- 新增数据模型: user, company, reconciliation_task, field_mapping, uploaded_file 等
- 新增服务层: ai_recognizer, file_parser, file_storage, mapping, reconciliation 等
- 添加数据库迁移脚本

前端:
- 新增登录页面和仪表盘页面
- 新增任务列表、任务详情、字段映射页面
- 新增异常处理页面和规则设置页面
- 新增 API 代理路由 /api/[...path]
- 新增 UI 组件库 (button, card, dialog, input, table 等)
- 新增 auth 组件 (ProtectedRoute, PermissionGate)
- 新增 layout 组件 (Header, Sidebar)
- 新增 mapping 组件 (FieldMappingTable, AISuggestionPanel)
- 新增 API 客户端和 hooks (useAsync, useToast, usePermission 等)
- 新增状态管理 (auth-store, company-store, ui-store)
- 集成 Tailwind CSS 和 shadcn/ui 组件库

其他:
- 添加 Alembic 数据库迁移配置
- 添加初始化示例数据脚本
- 更新项目文档

backend/app/models/company_rule.py

@@ -0,0 +1,57 @@
+"""
+企业规则模型
+
+用于存储企业自定义的映射规则，实现规则复用
+"""
+
+from datetime import datetime
+from enum import Enum
+from typing import Optional
+
+from sqlalchemy import ForeignKey, Integer, String, Boolean, DateTime, JSON
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from app.models.base import BaseModel
+
+
+class RuleType(str, Enum):
+    """规则类型"""
+    FIELD_MAPPING = "FIELD_MAPPING"  # 字段映射规则
+    ACCOUNT_MAPPING = "ACCOUNT_MAPPING"  # 科目映射规则
+    DEPARTMENT_MAPPING = "DEPARTMENT_MAPPING"  # 部门映射规则
+
+
+class RuleStatus(str, Enum):
+    """规则状态"""
+    ACTIVE = "ACTIVE"  # 启用
+    INACTIVE = "INACTIVE"  # 停用
+
+
+class CompanyRule(BaseModel):
+    """
+    企业规则模型
+
+    存储企业自定义的业务规则，用于自动应用
+    """
+
+    __tablename__ = "company_rules"
+
+    company_id: Mapped[int] = mapped_column(Integer, ForeignKey("companies.id"), nullable=False, index=True)
+    rule_type: Mapped[str] = mapped_column(String(50), nullable=False, index=True, comment="规则类型")
+    match_condition: Mapped[dict] = mapped_column(JSON, nullable=False, comment="匹配条件")
+    target_value: Mapped[str] = mapped_column(String(100), nullable=False, comment="目标值")
+    priority: Mapped[int] = mapped_column(Integer, nullable=False, default=0, comment="优先级，数字越大优先级越高")
+    status: Mapped[str] = mapped_column(String(20), nullable=False, default=RuleStatus.ACTIVE.value, comment="状态")
+    description: Mapped[Optional[str]] = mapped_column(String(500), nullable=True, comment="规则描述")
+    match_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0, comment="匹配次数")
+    last_used_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
+    created_by: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("users.id"), nullable=True)
+    updated_by: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("users.id"), nullable=True)
+
+    # 关系
+    company = relationship("Company", back_populates="rules")
+    creator = relationship("User", foreign_keys=[created_by])
+    updater = relationship("User", foreign_keys=[updated_by])
+
+    def __repr__(self) -> str:
+        return f"<CompanyRule(type='{self.rule_type}', target='{self.target_value}', priority={self.priority})>"