Update app/models/class_.py

app/models/class_.py

@@ -32,6 +32,9 @@ class Class(Base):
 
     classes_per_week = Column(Integer, nullable=False, default=1)
     max_students = Column(Integer, nullable=False, default=20)
+    
+    # Coach assignment
+    coach_email = Column(String(255), nullable=True, index=True)
 
     # No membership plan link anymore – kept fully independent
     # (plan_id / membership_plan_id removed)