refactor: remove unnecessary useMemo calls across components

Replace over-cached simple computations with direct expressions:

- popup/App.tsx: getEntryPointType() and routerConfig (values are stable)
- Dashboard/index.tsx: visibleSet, visibleFeatures, recentFeatures
  (Set creation + array filter/map are cheaper than useMemo overhead)
- useTextStatistics.ts: getTextStats(text) (simple string processing)
- ThemeModeProvider.tsx: contextValue object (setMode is stable via useCallback)

-39 lines, +28 lines (net -11 lines)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/entrypoints/popup/App.tsx

@@ -3,25 +3,21 @@ import TopBar from '@/components/TopBar';
 import RouterContainer from '@/components/RouterContainer';
 import ErrorBoundary from '@/components/ErrorBoundary';
 import { getEntryPointType } from '@/config/features';
-import { useMemo } from 'react';
-
 export default function App() {
-  const entryType = useMemo(() => getEntryPointType(), []);
+  const entryType = getEntryPointType();
 
-  const routerConfig = useMemo(() => {
-    if (entryType === 'tab') {
-      return {
-        syncKey: 'app/tabRoute' as const,
-        visiblePagesKey: 'app/tabVisiblePages' as const,
-        pageOrderKey: 'app/tabPageOrder' as const,
-      };
-    }
-    return {
-      syncKey: 'app/popupRoute' as const,
-      visiblePagesKey: 'app/popupVisiblePages' as const,
-      pageOrderKey: 'app/popupPageOrder' as const,
-    };
-  }, [entryType]);
+  const routerConfig =
+    entryType === 'tab'
+      ? {
+          syncKey: 'app/tabRoute' as const,
+          visiblePagesKey: 'app/tabVisiblePages' as const,
+          pageOrderKey: 'app/tabPageOrder' as const,
+        }
+      : {
+          syncKey: 'app/popupRoute' as const,
+          visiblePagesKey: 'app/popupVisiblePages' as const,
+          pageOrderKey: 'app/popupPageOrder' as const,
+        };
 
   return (
     <RouterProvider

src/pages/Dashboard/index.tsx

@@ -1,7 +1,6 @@
 import { useRouter } from '@/providers/RouterProvider';
 import { getFeatureByKey } from '@/config/features';
 import type { PageType } from '@/types/storage';
-import { useMemo } from 'react';
 import { useI18n } from '@/utils/chromeI18n';
 import { cn } from '@/lib/utils';
 
@@ -9,21 +8,17 @@ export default function Index() {
   const { navigateTo, visiblePages, pageOrder, recentlyUsedTools } = useRouter();
   const { t } = useI18n(['features']);
 
-  const visibleSet = useMemo(() => new Set<string>(visiblePages), [visiblePages]);
+  const visibleSet = new Set<string>(visiblePages);
 
-  const visibleFeatures = useMemo(() => {
-    return pageOrder
-      .filter((key) => visibleSet.has(key))
-      .map((key) => ({ key, feature: getFeatureByKey(key) }))
-      .filter((item) => item.feature?.themeColorKey && item.feature.icon != null);
-  }, [pageOrder, visibleSet]);
+  const visibleFeatures = pageOrder
+    .filter((key) => visibleSet.has(key))
+    .map((key) => ({ key, feature: getFeatureByKey(key) }))
+    .filter((item) => item.feature?.themeColorKey && item.feature.icon != null);
 
-  const recentFeatures = useMemo(() => {
-    return recentlyUsedTools
-      .filter((key) => visibleSet.has(key))
-      .map((key) => ({ key, feature: getFeatureByKey(key) }))
-      .filter((item) => item.feature?.themeColorKey && item.feature.icon != null);
-  }, [recentlyUsedTools, visibleSet]);
+  const recentFeatures = recentlyUsedTools
+    .filter((key) => visibleSet.has(key))
+    .map((key) => ({ key, feature: getFeatureByKey(key) }))
+    .filter((item) => item.feature?.themeColorKey && item.feature.icon != null);
 
   const showRecent = recentFeatures.length > 0;
 

src/pages/TextStatistics/useTextStatistics.ts

@@ -1,4 +1,4 @@
-import { useCallback, useMemo, useState } from 'react';
+import { useCallback, useState } from 'react';
 import { getTextStats, type TextStats } from '@/utils/textStatistics';
 import { useContextMenuData } from '@/utils/useContextMenuData';
 
@@ -17,7 +17,7 @@ export function useTextStatistics(): UseTextStatisticsReturn {
 
   useContextMenuData({ featureKey: 'textStatistics', onData: handleContextMenuData });
 
-  const stats = useMemo(() => getTextStats(text), [text]);
+  const stats = getTextStats(text);
 
   return { text, stats, setText };
 }

src/providers/ThemeModeProvider.tsx

@@ -1,12 +1,4 @@
-import {
-  createContext,
-  ReactNode,
-  useCallback,
-  useContext,
-  useEffect,
-  useMemo,
-  useState,
-} from 'react';
+import { createContext, ReactNode, useCallback, useContext, useEffect, useState } from 'react';
 import { browser } from 'wxt/browser';
 import { storageUtil } from '@/utils/chromeStorage';
 
@@ -141,12 +133,11 @@ export function ThemeModeProvider({ children }: ThemeModeProviderProps) {
     }
   }, [resolvedMode]);
 
-  const contextValue = useMemo(
-    () => ({ mode, resolvedMode, setMode }),
-    [mode, resolvedMode, setMode],
+  return (
+    <ThemeModeContext.Provider value={{ mode, resolvedMode, setMode }}>
+      {children}
+    </ThemeModeContext.Provider>
   );
-
-  return <ThemeModeContext.Provider value={contextValue}>{children}</ThemeModeContext.Provider>;
 }
 
 export function useThemeMode(): ThemeModeContextType {