add feed in / out button page and also button to redirect to button page

backend/apps/farms/models.py

@@ -24,6 +24,7 @@ class Site(models.Model):
 class Kandang(models.Model):
     kandang_id = models.BigAutoField(primary_key=True)
     kandang_name = models.CharField(max_length=30)
+    feed_in_button_urls = models.JSONField(default=list, blank=True)
     site = models.ForeignKey(Site, on_delete=models.CASCADE, related_name="kandangs")
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)