[component] Document is_idle condition

Author: clydebarrow

content/automations/actions.md

@@ -460,7 +460,21 @@ on_...:
 
 - **condition** (**Required**, [condition](#config-condition)): The condition to check.
 
-{{< anchor "lambda_condition" >}}
+### `component.is_idle` Condition
+
+This condition checks if a given component is idle. A component is considered to be idle if it has completed
+setup, has not been marked as failed, and is not currently being called by the loop task. This is useful for
+synchronizing actions with the state of the component, for example, an e-paper display component that requires
+a significant amount of time to update the display panel.
+
+```yaml
+on_...:
+  then:
+    - if:
+        condition:
+          component.is_idle: some_component
+        # ...
+```
 
 ### `lambda` Condition