Style: Use fixed height for monitoring images

- Changed from width to height constraint (250px)
- Ensures Dashboard and JSON endpoint images align properly
- Better visual consistency in side-by-side layout

Author: UntisSync

README.md

@@ -34,8 +34,8 @@
 ### Monitoring
 
 <p>
-  <img src="showcase/Dashboard1.png" width="400" alt="Status Dashboard">
-  <img src="showcase/JsonEndpoint_Example1.png" width="400" alt="JSON API Response">
+  <img src="showcase/Dashboard1.png" height="250" alt="Status Dashboard">
+  <img src="showcase/JsonEndpoint_Example1.png" height="250" alt="JSON API Response">
 </p>
 
 </div>