fix: improve diagram node readability and add UI to SonarQube scan

- Increase node width (160→220), height (40→50), spacing (90→120)
- Use SVG clipPath for text instead of character-count truncation
- Add UI sources, ESLint report, and sonar-scanner CLI to SonarQube workflow

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-app/src/main/java/com/cameleer3/server/app/diagram/ElkDiagramRenderer.java

@@ -53,12 +53,12 @@ public class ElkDiagramRenderer implements DiagramRenderer {
     }
 
     private static final int PADDING = 20;
-    private static final int NODE_HEIGHT = 40;
-    private static final int NODE_WIDTH = 160;
+    private static final int NODE_HEIGHT = 50;
+    private static final int NODE_WIDTH = 220;
     private static final int COMPOUND_TOP_PADDING = 30;
     private static final int COMPOUND_SIDE_PADDING = 10;
     private static final int CORNER_RADIUS = 8;
-    private static final double NODE_SPACING = 90.0;
+    private static final double NODE_SPACING = 120.0;
     private static final double EDGE_SPACING = 20.0;
 
     // Blue: endpoints