chore: Prepare CRD versioning (#898)

* chore: Move crds.yaml file

* chore(helm): Adjust template files

* feat: Add conversion webhook

* chore: Add changelog entry

Author: Techassi

CHANGELOG.md

@@ -6,6 +6,7 @@ All notable changes to this project will be documented in this file.
 
 ### Added
 
+- Add conversion webhook ([#898]).
 - Support objectOverrides using `.spec.objectOverrides`.
   See [objectOverrides concepts page](https://docs.stackable.tech/home/nightly/concepts/overrides/#object-overrides) for details ([#885]).
 - Enable the [restart-controller](https://docs.stackable.tech/home/nightly/commons-operator/restarter/), so that the Pods are automatically restarted on config changes ([#888]).
@@ -33,6 +34,7 @@ All notable changes to this project will be documented in this file.
 [#888]: https://github.com/stackabletech/nifi-operator/pull/888
 [#893]: https://github.com/stackabletech/nifi-operator/pull/893
 [#894]: https://github.com/stackabletech/nifi-operator/pull/894
+[#898]: https://github.com/stackabletech/nifi-operator/pull/898
 
 ## [25.11.0] - 2025-11-07