Add screenshots to README

Author: tisto

backend/README.md

@@ -2,6 +2,8 @@
 
 The backend package for Keyword Manager for Plone — a Plone 6 add-on that lets content editors rename, merge, and delete keywords (subjects/tags) across a site, with all content updated automatically. See also the frontend package [@kitconcept/volto-keywordmanager](https://www.npmjs.com/package/@kitconcept/volto-keywordmanager).
 
+![Keyword Manager](https://raw.githubusercontent.com/kitconcept/kitconcept-keywordmanager/main/assets/Keyword_Manager.png)
+
 ## Features
 
 - **Browse all keywords** currently in use, sorted by name or by number of occurrences.

frontend/README.md

@@ -19,6 +19,8 @@ The frontend package for Keyword Manager for Plone — a Plone 6 add-on that let
 > [!WARNING]
 > This add-on is designed to work with [volto-light-theme](https://github.com/kitconcept/volto-light-theme). If your site uses a different theme, you will need to provide your own styles or import the existing ones manually: `import "@kitconcept/volto-keywordmanager/theme/_main.scss"`. See the [Volto theming documentation](https://6.docs.plone.org/volto/theming/theming-a-base-theme.html) for details.
 
+![Keyword Manager](https://raw.githubusercontent.com/kitconcept/kitconcept-keywordmanager/main/assets/Keyword_Manager.png)
+
 ## Installation
 
 To install your project, you must choose the method appropriate to your version of Volto.