feat: 实现城市手册项目需求 - 数据库模型

- 扩展 User 模型，添加角色和状态字段
- 创建 Region 模型（省市县乡村层级结构）
- 创建版主管理相关模型（申请、权限、支持、限制）
- 创建 Article 模型（文章 + 审核流程）
- 创建 FeaturedService 模型（特色服务 + 审核流程）
- 创建交互功能模型（评论、评分、点赞、收藏）
- 更新 Django settings 注册所有 apps
- 创建需求实施文档

完整实现需求文档中的 12 个核心数据表和审核流程

backend/apps/interactions/models.py

@@ -0,0 +1,159 @@
+from django.db import models
+from django.conf import settings
+
+
+class Comment(models.Model):
+    """Model for comments."""
+
+    AI_STATUS_CHOICES = [
+        ('pending', '待审核'),
+        ('approved', '通过'),
+        ('rejected', '拒绝'),
+    ]
+
+    TARGET_TYPE_CHOICES = [
+        ('article', '文章'),
+        ('service', '特色服务'),
+    ]
+
+    content = models.TextField(verbose_name='评论内容')
+    target_type = models.CharField(
+        max_length=20,
+        choices=TARGET_TYPE_CHOICES,
+        verbose_name='评论对象类型'
+    )
+    target_id = models.PositiveIntegerField(verbose_name='评论对象ID')
+    author = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='comments',
+        verbose_name='评论者'
+    )
+    ai_status = models.CharField(
+        max_length=20,
+        choices=AI_STATUS_CHOICES,
+        default='pending',
+        verbose_name='AI审核状态'
+    )
+    ai_rejection_reason = models.TextField(null=True, blank=True, verbose_name='AI拒绝原因')
+    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
+
+    class Meta:
+        db_table = 'comments'
+        verbose_name = '评论'
+        verbose_name_plural = '评论'
+        ordering = ['-created_at']
+
+    def __str__(self):
+        return f'{self.author.username} on {self.target_type} {self.target_id}'
+
+    def approve_ai(self):
+        """Approve comment by AI."""
+        self.ai_status = 'approved'
+        self.save()
+
+    def reject_ai(self, reason):
+        """Reject comment by AI."""
+        self.ai_status = 'rejected'
+        self.ai_rejection_reason = reason
+        self.save()
+
+
+class Rating(models.Model):
+    """Model for ratings."""
+
+    TARGET_TYPE_CHOICES = [
+        ('region', '城市'),
+        ('service', '特色服务'),
+    ]
+
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='ratings',
+        verbose_name='用户'
+    )
+    target_type = models.CharField(
+        max_length=20,
+        choices=TARGET_TYPE_CHOICES,
+        verbose_name='评分对象类型'
+    )
+    target_id = models.PositiveIntegerField(verbose_name='评分对象ID')
+    score = models.PositiveSmallIntegerField(verbose_name='评分值')
+    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
+
+    class Meta:
+        db_table = 'ratings'
+        verbose_name = '评分'
+        verbose_name_plural = '评分'
+        unique_together = ['user', 'target_type', 'target_id']
+        ordering = ['-created_at']
+
+    def __str__(self):
+        return f'{self.user.username} rated {self.target_type} {self.target_id}: {self.score}'
+
+
+class Like(models.Model):
+    """Model for likes."""
+
+    TARGET_TYPE_CHOICES = [
+        ('article', '文章'),
+        ('service', '特色服务'),
+    ]
+
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='likes',
+        verbose_name='用户'
+    )
+    target_type = models.CharField(
+        max_length=20,
+        choices=TARGET_TYPE_CHOICES,
+        verbose_name='点赞对象类型'
+    )
+    target_id = models.PositiveIntegerField(verbose_name='点赞对象ID')
+    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
+
+    class Meta:
+        db_table = 'likes'
+        verbose_name = '点赞'
+        verbose_name_plural = '点赞'
+        unique_together = ['user', 'target_type', 'target_id']
+        ordering = ['-created_at']
+
+    def __str__(self):
+        return f'{self.user.username} likes {self.target_type} {self.target_id}'
+
+
+class Favorite(models.Model):
+    """Model for favorites."""
+
+    TARGET_TYPE_CHOICES = [
+        ('region', '城市'),
+        ('service', '特色服务'),
+    ]
+
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='favorites',
+        verbose_name='用户'
+    )
+    target_type = models.CharField(
+        max_length=20,
+        choices=TARGET_TYPE_CHOICES,
+        verbose_name='收藏对象类型'
+    )
+    target_id = models.PositiveIntegerField(verbose_name='收藏对象ID')
+    created_at = models.DateTimeField(auto_now_add=True, verbose_name='创建时间')
+
+    class Meta:
+        db_table = 'favorites'
+        verbose_name = '收藏'
+        verbose_name_plural = '收藏'
+        unique_together = ['user', 'target_type', 'target_id']
+        ordering = ['-created_at']
+
+    def __str__(self):
+        return f'{self.user.username} favorited {self.target_type} {self.target_id}'