chore: 迁移到 pnpm 并更新打包与测试文档

- 用 pnpm 替换 npm，锁定 pnpm@10.33.0，删除 package-lock.json 相关说明
- package.json 将渲染层依赖移入 devDependencies，减小 app.asar 体积
- 新增 electron:smoke 冒烟脚本与 icon 生成脚本
- win 平台设置 AppUserModelID，修复任务栏图标归组
- 清理 tsBuildInfoFile 输出路径至 node_modules/.tmp
- 更新测试断言以匹配画幅遮罩、取景器缩放与模型库外部资产行为
- README 与打包指南补充 pnpm、镜像与常见问题说明

build-electron.bat

@@ -1,4 +1,8 @@
 @echo off
+setlocal
+cd /d "%~dp0"
+
+rem Electron / electron-builder 二进制下载走国内镜像
 set ELECTRON_MIRROR=https://npmmirror.com/mirrors/electron/
 set ELECTRON_BUILDER_BINARIES_MIRROR=https://npmmirror.com/mirrors/electron-builder-binaries/
 
@@ -7,7 +11,7 @@ echo   StoryAI 3D Director Desk - Package Tool
 echo ========================================
 echo.
 
-echo [0/4] Cleaning old files...
+echo [0/4] Cleaning old output...
 if exist "release" (
     rmdir /s /q "release" 2>nul
     if exist "release" (
@@ -16,21 +20,22 @@ if exist "release" (
         exit /b 1
     )
 )
-if exist "node_modules\electron" (
-    rmdir /s /q "node_modules\electron" 2>nul
-)
 
-echo [1/4] Installing dependencies...
-call npm install
+rem 不要再单独删除 node_modules 里的某个包（例如 node_modules\electron）。
+rem 绕过包管理器删包，会让 pnpm 仍以为该依赖已安装，反而产出缺失/空壳的依赖目录。
+rem 需要重装时统一执行 pnpm install。
+
+echo [1/4] Installing dependencies with pnpm...
+call pnpm install
 if errorlevel 1 (
-    echo Install failed!
+    echo Install failed! Install pnpm first:  npm i -g pnpm
     pause
     exit /b 1
 )
 
 echo.
 echo [2/4] Building frontend...
-call npm run build
+call pnpm run build
 if errorlevel 1 (
     echo Build failed!
     pause
@@ -39,7 +44,7 @@ if errorlevel 1 (
 
 echo.
 echo [3/4] Packaging to exe...
-call npx electron-builder --win
+call pnpm exec electron-builder --win
 if errorlevel 1 (
     echo Package failed!
     pause