Implement `Power up` part of hive power management

Requires:

1. !298 (merged) (to change the inputs to the new)

clive/__private/ui/operations/hive_power_management/common_hive_power/additional_info_widgets.py

@@ -88,10 +88,8 @@ class APR(DynamicLabel):
     """
 
     def __init__(self, provider: HivePowerDataProvider):
-        super().__init__(obj_to_watch=provider, attribute_name="_content", callback=self._get_apr)
+        super().__init__(obj_to_watch=provider, attribute_name="_content", callback=self._get_apr, init=False)
         self._provider = provider
 
     def _get_apr(self, content: HivePowerData) -> str:
-        if self._provider.is_content_set:
-            return f"APR interest for HP/VESTS ≈ {content.current_hp_apr} %"
-        return "loading..."
+        return f"APR interest for HP/VESTS ≈ {content.current_hp_apr} %"