docs(readme): 编写项目README文档，描述功能与架构

- 完整撰写玉宗珠宝设计大师项目README，介绍项目概况及核心功能
- 说明用户认证系统实现及优势，包含JWT鉴权和密码加密细节
- 详细描述品类管理系统，支持多流程类型和多种玉石品类
- 说明设计图生成方案及技术，包含Pillow生成示例及字体支持
- 介绍设计管理功能，支持分页浏览、预览、下载和删除设计
- 个人信息管理模块说明，涵盖昵称、手机号、密码的安全修改
- 绘制业务流程图和关键数据流图，清晰展现系统架构与数据流
- 提供详细API调用链路及参数说明，涵盖用户、品类、设计接口
- 列明技术栈及版本，包含前后端框架、ORM、认证、加密等工具
- 展示目录结构，标明后端与前端项目布局
- 规划本地开发环境与启动步骤，包括数据库初始化及运行命令
- 说明服务器部署流程和Nginx配置方案
- 详细数据库表结构说明及环境变量配置指导
- 汇总常用开发及测试命令，方便开发调试与部署管理

backend/app/models/__init__.py

@@ -0,0 +1,17 @@
+"""
+数据库模型
+导出所有模型，确保 Base.metadata 包含所有表
+"""
+from ..database import Base
+from .user import User
+from .category import Category, SubType, Color
+from .design import Design
+
+__all__ = [
+    "Base",
+    "User",
+    "Category",
+    "SubType",
+    "Color",
+    "Design"
+]

backend/app/models/category.py

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+"""
+品类相关模型
+包含：品类、子类型、颜色
+"""
+from sqlalchemy import Column, Integer, String, ForeignKey
+from sqlalchemy.orm import relationship
+
+from ..database import Base
+
+
+class Category(Base):
+    """品类表"""
+    __tablename__ = "categories"
+
+    id = Column(Integer, primary_key=True, autoincrement=True, comment="品类ID")
+    name = Column(String(50), nullable=False, comment="品类名称")
+    icon = Column(String(255), nullable=True, comment="品类图标")
+    sort_order = Column(Integer, default=0, comment="排序")
+    flow_type = Column(String(20), nullable=False, comment="流程类型：full/size_color/simple")
+
+    # 关联关系
+    sub_types = relationship("SubType", back_populates="category")
+    colors = relationship("Color", back_populates="category")
+    designs = relationship("Design", back_populates="category")
+
+    def __repr__(self):
+        return f"<Category(id={self.id}, name='{self.name}')>"
+
+
+class SubType(Base):
+    """子类型表"""
+    __tablename__ = "sub_types"
+
+    id = Column(Integer, primary_key=True, autoincrement=True, comment="子类型ID")
+    category_id = Column(Integer, ForeignKey("categories.id"), nullable=False, comment="所属品类")
+    name = Column(String(50), nullable=False, comment="名称")
+    description = Column(String(255), nullable=True, comment="描述")
+    preview_image = Column(String(255), nullable=True, comment="预览图")
+    sort_order = Column(Integer, default=0, comment="排序")
+
+    # 关联关系
+    category = relationship("Category", back_populates="sub_types")
+    designs = relationship("Design", back_populates="sub_type")
+
+    def __repr__(self):
+        return f"<SubType(id={self.id}, name='{self.name}')>"
+
+
+class Color(Base):
+    """颜色表"""
+    __tablename__ = "colors"
+
+    id = Column(Integer, primary_key=True, autoincrement=True, comment="颜色ID")
+    category_id = Column(Integer, ForeignKey("categories.id"), nullable=False, comment="适用品类")
+    name = Column(String(50), nullable=False, comment="颜色名称")
+    hex_code = Column(String(7), nullable=False, comment="色值")
+    sort_order = Column(Integer, default=0, comment="排序")
+
+    # 关联关系
+    category = relationship("Category", back_populates="colors")
+    designs = relationship("Design", back_populates="color")
+
+    def __repr__(self):
+        return f"<Color(id={self.id}, name='{self.name}', hex_code='{self.hex_code}')>"

backend/app/models/design.py

@@ -0,0 +1,39 @@
+"""
+设计作品模型
+"""
+from sqlalchemy import Column, BigInteger, Integer, String, Text, DateTime, ForeignKey
+from sqlalchemy.sql import func
+from sqlalchemy.orm import relationship
+
+from ..database import Base
+
+
+class Design(Base):
+    """设计作品表"""
+    __tablename__ = "designs"
+
+    id = Column(BigInteger, primary_key=True, autoincrement=True, comment="设计ID")
+    user_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, comment="用户ID")
+    category_id = Column(Integer, ForeignKey("categories.id"), nullable=False, comment="品类ID")
+    sub_type_id = Column(Integer, ForeignKey("sub_types.id"), nullable=True, comment="子类型ID")
+    color_id = Column(Integer, ForeignKey("colors.id"), nullable=True, comment="颜色ID")
+    prompt = Column(Text, nullable=False, comment="设计需求")
+    carving_technique = Column(String(50), nullable=True, comment="雕刻工艺")
+    design_style = Column(String(50), nullable=True, comment="设计风格")
+    motif = Column(String(100), nullable=True, comment="题材纹样")
+    size_spec = Column(String(100), nullable=True, comment="尺寸规格")
+    surface_finish = Column(String(50), nullable=True, comment="表面处理")
+    usage_scene = Column(String(50), nullable=True, comment="用途场景")
+    image_url = Column(String(255), nullable=True, comment="设计图URL")
+    status = Column(String(20), default="generating", comment="状态")
+    created_at = Column(DateTime, server_default=func.now(), comment="创建时间")
+    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now(), comment="更新时间")
+
+    # 关联关系
+    user = relationship("User", back_populates="designs")
+    category = relationship("Category", back_populates="designs")
+    sub_type = relationship("SubType", back_populates="designs")
+    color = relationship("Color", back_populates="designs")
+
+    def __repr__(self):
+        return f"<Design(id={self.id}, status='{self.status}')>"

backend/app/models/user.py

@@ -0,0 +1,28 @@
+"""
+用户模型
+"""
+from sqlalchemy import Column, BigInteger, String, DateTime
+from sqlalchemy.sql import func
+from sqlalchemy.orm import relationship
+
+from ..database import Base
+
+
+class User(Base):
+    """用户表"""
+    __tablename__ = "users"
+
+    id = Column(BigInteger, primary_key=True, autoincrement=True, comment="用户ID")
+    username = Column(String(50), unique=True, nullable=False, comment="用户名")
+    phone = Column(String(20), unique=True, nullable=True, comment="手机号")
+    hashed_password = Column(String(255), nullable=False, comment="加密密码")
+    nickname = Column(String(50), nullable=True, comment="昵称")
+    avatar = Column(String(255), nullable=True, comment="头像URL")
+    created_at = Column(DateTime, server_default=func.now(), comment="创建时间")
+    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now(), comment="更新时间")
+
+    # 关联关系
+    designs = relationship("Design", back_populates="user")
+
+    def __repr__(self):
+        return f"<User(id={self.id}, username='{self.username}')>"