fix: 非高亮的边禁用交互，无法被选中

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Co-Authored-By: Claude <noreply@anthropic.com>

script/visualization/src/style.css

@@ -109,6 +109,7 @@
   .graph-link.dimmed,
   .walked-link.dimmed {
     stroke-opacity: 0.03 !important;
+    pointer-events: none;
   }
 
   /* 分数标签置灰 */