Application buttons - Allow adding & hiding buttons locally

Template authors might add multiple IDEs and editors to cater to a broader group. However, as an individual developer, I might only be interested in VS Code, not JetBrains IDEs. Thus, one can show and hide icons based on personal, locally stored preferences. These can be preferences stored in "global" settings, like the HTTP headers, or on a per workspace level.

该 issue 未指明文件、测试或入口点。首先定位应用按钮的渲染逻辑以及现有的全局或工作区偏好设置存储，然后确定模板提供的按钮是如何表示的。当用户可以在本地添加或隐藏按钮，并且偏好设置支持全局或按工作区配置时，即视为完成。

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