Readded fk constraint for conversion_guests

src/alpine_bits_python/db.py

@@ -622,12 +622,15 @@ class Conversion(Base):
     updated_at = Column(DateTime(timezone=True))  # When this record was last updated
 
     # Table constraints
-    # Note: The relationship to ConversionGuest is handled via SQLAlchemy ORM
-    # by matching (hotel_id, guest_id) pairs, no DB-level FK constraint needed
     __table_args__ = (
         UniqueConstraint(
             "hotel_id", "pms_reservation_id", name="uq_conversion_hotel_reservation"
         ),
+        ForeignKeyConstraint(
+            ["hotel_id", "guest_id"],
+            ["conversion_guests.hotel_id", "conversion_guests.guest_id"],
+            name="fk_conversions_guest",
+        ),
     )
 
     # Relationships