Add changelog for v0.2.0

Author: julianbrost

CHANGELOG.md

@@ -1,5 +1,34 @@
 # Icinga Notifications Changelog
 
+## 0.2.0 (2025-11-18)
+
+This release changes how Icinga Notifications interacts with sources. In
+particular, the evaluation of object filters is now performed by the source,
+allowing it to use a custom filter syntax and provide more advanced filter
+options than previously provided by Icinga Notifications. The previously
+built-in Icinga 2 source is removed and replaced by an implementation inside
+Icinga DB v1.5.0 that now allows filters based on custom variables, for
+example.
+
+This update requires manual steps including a schema upgrade and configuration
+changes. Please make sure to read the
+[upgrading documentation](https://icinga.com/docs/icinga-notifications/latest/doc/04-Upgrading/#upgrading-to-icinga-notifications-v020)
+and follow it carefully.
+
+* Let sources evaluate the object filters from event rules. #324 #356 #354
+* Allow setting a custom username for source authentication. #338
+* Add /incidents API endpoint allowing sources to query their open incidents. #361
+* Fix issues where changes to channels and event rules weren't applied to the
+  running configuration correctly. #333 #334
+* Move all debug HTTP endpoints to common /debug prefix. #308
+* Reorder history events around mute and unmute events. #346
+* Extend database schema for new Icinga Notifications Web functionality. #216 #344
+* Documentation: Adapt the minimum MariaDB and MySQL versions to the
+  requirements of Icinga Notifications Web. #287
+* Documentation: Add information how to view additional log message fields with
+  systemd journald. #274
+
+
 ## 0.1.1 (2024-07-29)
 
 This is a small bug fix release with the main change being a fix for logging to the systemd journal.