docs(example): add trame slicer MRHead screenshot

Author: finetjul

docs/vitepress/assets/images/apps/trame-slicer-mrhead.png

@@ -2,4 +2,5 @@
 
 Please [reach out to Kitware](https://www.kitware.com/contact/) for more details regarding that framework.
 
-![trame-slicer](/assets/images/apps/trame-slicer.png)
+![trame-slicer multiple segments](/assets/images/apps/trame-slicer.png)
+![trame-slicer MRHead](/assets/images/apps/trame-slicer-mrhead.png)