重构：Wails升级/mermaid主题切换/代码高亮修复/文件系统UI重构

- Wails v2.12.0升级（App绑定新增API、runtime类型扩展）
- 修复mermaid暗色主题切换渲染失败（SVG textContent污染→data-mermaid-src保存源码）
- 修复代码高亮全语言失效（languageMap静态白名单替代运行时hljs检查）
- 文件系统：FileListPanel重写、FileItemRow合并删除、Toolbar简化
- 新增剪贴板图片粘贴（Ctrl+V粘贴图片到当前目录）
- 死代码清理：DeviceTest/errorHandler/useLocalStorage移除
- MarkdownEditor优化、theme store增强、CodeMirror加载器精简

web/package.json

@@ -28,8 +28,6 @@
     "@codemirror/state": "^6.5.3",
     "@codemirror/theme-one-dark": "^6.1.3",
     "@codemirror/view": "^6.39.8",
-    "@types/highlight.js": "^9.12.4",
-    "@types/mermaid": "^9.1.0",
     "highlight.js": "^11.11.1",
     "mammoth": "^1.11.0",
     "marked": "^17.0.1",
@@ -39,6 +37,8 @@
     "xlsx": "^0.18.5"
   },
   "devDependencies": {
+    "@types/highlight.js": "^9.12.4",
+    "@types/mermaid": "^9.1.0",
     "@vitejs/plugin-vue": "^6.0.3",
     "unplugin-auto-import": "^0.18.3",
     "unplugin-vue-components": "^0.27.4",