Find diffs inside <bpmn:extensionElements>

### Is your feature request related to a problem? Please describe.

Changes(any, e.g. updated, added/removed) in camunda elements under are not recognized, even is Camunda Moddle is added and finds diffs in camunda attributes on main level well

Tried also via https://demo.bpmn.io/diff, maybe it`s just some old version is there. Currently looking for similar tool for my project.

### Describe the solution you'd like

Add precise elements check for diffs inside same as other elements

### Describe alternatives you've considered

nope

### Additional context

bpmn example for tests:

```xml

in2
in3
out2

```

Reproduce the issue with the supplied BPMN XML and Camunda Moddle, comparing documents whose camunda:extensionElements contents are added, removed, or updated. Inspect the diff handling for bpmn:extensionElements; done when nested Camunda element changes are reported like changes to top-level Camunda attributes.

Written by the indexing model from the issue text.