Bug: useVxeDrawer 嵌套 useVxeGrid 后，Grid 设置为 showOverflow: 'tooltip' 后，因 useVxeDrawer z-index 太高被遮盖

### Version Vben Admin V5 ### Describe the bug? useVxeDrawer 嵌套 useVxeGrid 后，Grid 设置为 showOverflow: 'tooltip' 后，因 useVxeDrawer z-index 太高被遮盖 ### Reproduction 官方代码即可复现 ### System Info ```shell System: OS: macOS 26.3.1 CPU: (8) arm64 Apple M2 Memory: 168.91 MB / 16.00 GB Shell: 5.9 - /bin/zsh Binaries: Node: 25.5.0 - /Users/zxj/.nvm/versions/node/v25.5.0/bin/node npm: 11.8.0 - /Users/zxj/.nvm/versions/node/v25.5.0/bin/npm pnpm: 10.28.2 - /Users/zxj/.nvm/versions/node/v25.5.0/bin/pnpm Browsers: Chrome: 148.0.7778.179 Safari: 26.3.1 ``` ### Relevant log output ```shell ``` ### Validations - [x] Read the [docs](https://doc.vben.pro/) - [x] Ensure the code is up to date. (Some issues have been fixed in the latest version) - [x] I have searched the [existing issues](https://github.com/vbenjs/vue-vben-admin/issues) and checked that my issue does not duplicate any existing issues. - [x] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/vbenjs/vue-vben-admin/discussions) or join our [Discord Chat Server](https://discord.gg/8GuAdwDhj6). - [x] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.