fix: increase graph container height to 700px on mobile

frontend/src/components/KnowledgeGraph.css

@@ -443,8 +443,8 @@
   .graph-network-container {
     padding-left: 0 !important;
     border-radius: 16px !important;
-    height: 600px !important;
-    min-height: 600px !important;
+    height: 700px !important;
+    min-height: 700px !important;
     width: 100% !important;
     flex: none !important;
     position: relative !important;

frontend/src/components/KnowledgeGraph.jsx

@@ -56,7 +56,7 @@ function KnowledgeGraph({ refreshTick }) {
         const { width, height } = entry.contentRect;
         const isMobile = window.innerWidth < 768;
         const adjustedWidth = isMobile ? (window.innerWidth - 32) : width;
-        const adjustedHeight = isMobile ? 600 : height;
+        const adjustedHeight = isMobile ? 700 : height;
         setDimensions({ width: adjustedWidth || 800, height: adjustedHeight || 500 });
       }
     });