Add use case for accessibility signals

Author: ntrogh

release-notes/v1_96.md

@@ -139,7 +139,9 @@ TODO@Tyriar
 
 ### Code Action accessibility signals
 
-We added accessibility signals to indicate that a Code Action was triggered or applied. You can enable these signals with the `setting(accessibility.signals.codeActionTriggered)` and `setting(accessibility.signals.codeActionApplied)` settings.
+Some code actions can take a long time to complete, for example a quick fix to generate the alt text for an image by calling an external service. It might not be obvious when they were triggered or when they're fully applied. Therefore, we added accessibility signals to indicate that a code action was triggered or applied.
+
+You can enable these signals with the `setting(accessibility.signals.codeActionTriggered)` and `setting(accessibility.signals.codeActionApplied)` settings.
 
 ### Automatic focus management in the REPL