fix: use conditional require for echarts-wordcloud instead of dynamic import

Dynamic import was async and wordcloud plugin wasn't loaded before
setOption was called. Now uses synchronous require() guarded by
typeof window check to avoid SSR crash.

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

frontend/src/frameworks/components/charts/EChartsBase.tsx

@@ -2,6 +2,8 @@
 
 import React, { useEffect, useRef } from 'react';
 import * as echarts from 'echarts';
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+if (typeof window !== 'undefined') { require('echarts-wordcloud'); }
 import { useThemeStore } from '@/adapters/state/zustand/themeStore';
 
 // ---------------------------------------------------------------------------
@@ -41,11 +43,6 @@ export const EChartsBase: React.FC<EChartsBaseProps> = ({
   const chartRef = useRef<echarts.ECharts | null>(null);
   const currentTheme = useThemeStore((s) => s.currentTheme);
 
-  // Load echarts-wordcloud plugin on client side only
-  useEffect(() => {
-    import('echarts-wordcloud').catch(() => {});
-  }, []);
-
   // Init / re-init when theme changes
   useEffect(() => {
     if (!containerRef.current) return;