Function ul_sys::ulSettingsSetFileSystemPath

pub unsafe extern "C" fn ulSettingsSetFileSystemPath(
    settings: ULSettings, 
    path: ULString
)

Set the root file path for our file system, you should set this to the relative path where all of your app data is.

This will be used to resolve all file URLs, eg file:///page.html

@note The default path is "./assets/"

   This relative path is resolved using the following logic:
    - Windows: relative to the executable path
    - Linux:   relative to the executable path
    - macOS:   relative to YourApp.app/Contents/Resources/