feat (kanchou_petfountain): add compatible Fontanna product

PR #4349

custom_components/tuya_local/devices/kanchou_petfountain.yaml

@@ -2,6 +2,9 @@ name: Pet fountain
 products:
   - id: akln8rb04cav403q
     manufacturer: Kanchou
+  - id: cafirr70niv1hj2x
+    manufacturer: Fontanna Smart
+    model: FONT7-SMART-B
 entities:
   - entity: select
     translation_key: activation_mode