重构：Wails v3 迁移 + 前端目录规范化 + Sidebar滚动优化

- web/ → frontend/ 目录重命名（Wails v3 标准结构）
- main.go: Middleware 修复 custom.js 404 + DevTools 延迟启动
- Sidebar: 收藏夹内部独立滚动 + 帮助区块固定底部
- useFavorites.ts: longPressTimer const→let 修复 TypeError
- App.vue: Arco Tabs padding-top 覆盖
- build: config.yml / Taskfile.yml 对齐官方模板，devtools build tag
- 新增 v3 bindings、vite.config.js、跨平台构建配置

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

build/ios/entitlements.plist

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <!-- Development entitlements -->
+    <key>get-task-allow</key>
+    <true/>
+
+    <!-- App Sandbox -->
+    <key>com.apple.security.app-sandbox</key>
+    <true/>
+
+    <!-- Network access -->
+    <key>com.apple.security.network.client</key>
+    <true/>
+
+    <!-- File access (read-only) -->
+    <key>com.apple.security.files.user-selected.read-only</key>
+    <true/>
+</dict>
+</plist>