Group Genmapper Colors (#2891)

* Enhance D3.js Genmap Visualization and CSS Adjustments

               - Updated CSS to prevent static fill color for node text, allowing dynamic color assignment via JavaScript.
               - Reduced font size for node titles and adjusted max-width for better text fitting.
               - Introduced constants for node dimensions in JavaScript to improve maintainability and prevent text clipping.
               - Added functions for calculating text color based on background luminance to ensure better contrast and readability.

* Refactor genmap status color resolution into ensureStatusColor helper

Eliminates ~9 duplicate inline status color resolution blocks across both render paths by extracting a shared ensureStatusColor() helper. Removes redundant .style('fill') calls and stale CSS comments.

Author: kodinkat

dt-groups/genmap-d3.css

@@ -70,18 +70,16 @@
 /* Node Text */
 .group-genmap-chart .node text {
     font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
-    fill: #333;
     pointer-events: none;
     text-anchor: middle;
     dominant-baseline: middle;
 }
 
 /* Node Title - truncated text */
 .group-genmap-chart .node .node-title {
-    font-size: 11px;
+    font-size: 9px;
     font-weight: 500;
-    fill: #333;
-    max-width: 56px; /* Slightly less than node width for padding */
+    max-width: 68px; /* Slightly less than node width (72px) for padding */
 }
 
 /* Node Generation Text */
@@ -336,7 +334,7 @@
     }
 
     .group-genmap-chart .node text {
-        font-size: 10px;
+        font-size: 9px;
     }
 
     .genmap-popover {