Ensure cover state restore and transition timer handles are cancelled upon entity removal

Author: jeverley

zha/application/platforms/cover/__init__.py

@@ -209,6 +209,14 @@ def on_add(self) -> None:
             )
         )
 
+    async def on_remove(self) -> None:
+        """Cancel tasks and timers this entity owns."""
+        await super().on_remove()
+        if self._lift_transition_timer:
+            self._lift_transition_timer.cancel()
+        if self._tilt_transition_timer:
+            self._tilt_transition_timer.cancel()
+
     def restore_external_state_attributes(
         self,
         *,
@@ -233,10 +241,11 @@ def restore_external_state_attributes(
             return
 
         self._state = state
-        self._loop.call_later(
+        restored_state_timer = self._loop.call_later(
             DEFAULT_MOVEMENT_TIMEOUT,
             functools.partial(self._determine_cover_state, refresh=True),
         )
+        self._on_remove_callbacks.append(restored_state_timer.cancel)
 
     @property
     def supported_features(self) -> CoverEntityFeature: