web-directory-picker: Enforcing Use of the Official In-App Directory Browse Dialog

`web-directory-picker` is a composite plugin for DeepSeek Harness, intended to solve the styling mismatch between the native directory chooser and the Web interface. It applies composable patches to disable automatic detection and force the use of the product’s official built-in component, ensuring the workspace selector opens a unified Web browse dialog and delivers a consistent localized experience. Both installation and uninstallation require restarting the DSH process, and it contains no runtime code.