feat(公开内容): 添加临时留言功能，留言保留10分钟，显示用户名、内容、时间和来源IP

core/models.py

@@ -262,3 +262,20 @@ class PublicContent(models.Model):
     
     def __str__(self):
         return f"{self.type.name} - {self.title}"
+
+
+class TempMessage(models.Model):
+    """临时留言"""
+    username = models.CharField(max_length=20, blank=True, null=True, verbose_name="用户名")
+    content = models.CharField(max_length=1000, verbose_name="内容")
+    ip_address = models.GenericIPAddressField(blank=True, null=True, verbose_name="来源IP")
+    created_at = models.DateTimeField(auto_now_add=True, verbose_name="创建时间")
+    expire_at = models.DateTimeField(blank=True, null=True, verbose_name="过期时间")
+
+    class Meta:
+        verbose_name = "临时留言"
+        verbose_name_plural = "临时留言"
+        ordering = ['-created_at']
+
+    def __str__(self):
+        return f"{self.username or '匿名'} - {self.content[:20]}..."