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/android/app/build.gradle

@@ -0,0 +1,63 @@
+plugins {
+    id 'com.android.application'
+}
+
+android {
+    namespace 'com.wails.app'
+    compileSdk 34
+
+    buildFeatures {
+        buildConfig = true
+    }
+
+    defaultConfig {
+        applicationId "com.wails.app"
+        minSdk 21
+        targetSdk 34
+        versionCode 1
+        versionName "1.0"
+
+        // Configure supported ABIs
+        ndk {
+            abiFilters 'arm64-v8a', 'x86_64'
+        }
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+        debug {
+            debuggable true
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_11
+        targetCompatibility JavaVersion.VERSION_11
+    }
+
+    // Source sets configuration
+    sourceSets {
+        main {
+            // JNI libraries are in jniLibs folder
+            jniLibs.srcDirs = ['src/main/jniLibs']
+            // Assets for the WebView
+            assets.srcDirs = ['src/main/assets']
+        }
+    }
+
+    // Packaging options
+    packagingOptions {
+        // Don't strip Go symbols in debug builds
+        doNotStrip '*/arm64-v8a/libwails.so'
+        doNotStrip '*/x86_64/libwails.so'
+    }
+}
+
+dependencies {
+    implementation 'androidx.appcompat:appcompat:1.6.1'
+    implementation 'androidx.webkit:webkit:1.9.0'
+    implementation 'com.google.android.material:material:1.11.0'
+}