Add the method to add destionation to a source.

tui_rsync/models/models.py

@@ -76,12 +76,20 @@ class Source(BaseModel):
             destinations=[],
             args=src_sync_cmd
         )
+
         for destination in destinations:
-            des_path, _ = Path.get_or_create(path=destination)
-            src_des, _ = Destination.get_or_create(source=src, path=des_path)
+            src.add_destionation(destination)
+
         src.save()
         return src
 
+    def add_destionation(self, destination):
+        destination_path, _ = Path.get_or_create(path=destination)
+        src_destination, _ = Destination.get_or_create(
+            source=self,
+            path=destination_path
+        )
+
     def update_label(self, new_label):
         self.label = new_label
         self.save()