Send tab defaults with presets.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/models/tab.py

@@ -9,7 +9,8 @@ class Tab(Model):
         self[next_id] = {
             "name": name,
             "names": names if names else [],
-            "presets": presets if presets else []
+            "presets": presets if presets else [],
+            "default_preset": None
         }
         self.save()
         return next_id