Update release notes

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

RELEASE_NOTES.md

@@ -2,21 +2,22 @@
 
 ## Summary
 
-<!-- Here goes a general summary of what this release is about -->
+This release introduces a more flexible and powerful mechanism for managing dispatch events with new strategies for merging intervals, enhanced customization options, and better overall alignment with evolving SDK dependencies. It also simplifies actor initialization while maintaining robust support for diverse dispatch scenarios.
 
 ## Upgrading
 
 * Two properties have been replaced by methods that require a type as parameter.
     * `Dispatcher.lifecycle_events` has been replaced by the method `Dispatcher.new_lifecycle_events_receiver(self, dispatch_type: str)`.
     * `Dispatcher.running_status_change` has been replaced by the method `Dispatcher.new_running_state_event_receiver(self, dispatch_type: str, unify_running_intervals: bool)`.
 * The managing actor constructor no longer requires the `dispatch_type` parameter. Instead you're expected to pass the type to the new-receiver function.
+* The `DispatchManagingActor` class has been renamed to `DispatchActorsService`.
+    * It's interface has been simplified and now only requires an actor factory and a running status receiver.
+    * It only supports a single actor at a time now.
+    * Refer to the updated [usage example](https://frequenz-floss.github.io/frequenz-dispatch-python/latest/reference/frequenz/dispatch/#frequenz.dispatch.DispatchActorsService) for more information.
 
 ## New Features
 
-* A new feature "merger strategy" (`MergeByType`, `MergeByTypeTarget`) has been added to the `Dispatcher.new_running_state_event_receiver` method. Using it, you can automatically merge & unify consecutive and overlapping dispatch start/stop events of the same type. E.g. dispatch `A` starting at 10:10 and ending at 10:30 and dispatch `B` starts at 10:30 until 11:00, with the feature enabled this would in total trigger one start event, one reconfigure event at 10:30 and one stop event at 11:00.
-
+* A new feature "merger strategy" (`MergeByType`, `MergeByTypeTarget`) has been added to the `Dispatcher.new_running_state_event_receiver` method. Using it, you can automatically merge and unify consecutive and overlapping dispatch start/stop events of the same type. For example:
+  * If dispatch A starts at 10:10 and ends at 10:30, and dispatch B starts at 10:30 and ends at 11:00, enabling the feature triggers one start event, one reconfigure event at 10:30, and one stop event at 11:00.
+* Support for user-defined strategies via `_MergeStrategy` has been introduced to allow customized merging behavior.
 * The SDK dependency was widened to allow versions up to (excluding) v1.0.0-rc1600.
-
-## Bug Fixes
-
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->