I'm looking for a script for a daily recurring workflow about Export Artboard as PDF

This is untested but should do the trick. And it needs some love in terms of pdf export options. unfortunately im not aware of any access to the "export for screens" dialog or functionality. But the same functionality should be doable with pdf save options. But im not sure what options you need for your use case.

function doDailyTask()
{
    var doc = app.activeDocument;
    app.executeMenuCommand("unlockAll");
    app.executeMenuCommand("deselectall");
    app.executeMenuCommand("selectallinartboard");
    app.executeMenuCommand("lock");
    app.executeMenuCommand("selectall");
    app.executeMenuCommand("clear");
    app.executeMenuCommand("unlockAll");
    app.executeMenuCommand("deselectall");
    deleteEmptyArtboards();
    exportPDF();
    
    function deleteEmptyArtboards()
    {
        var artboards = doc.artboards;
        for (var i = artboards.length - 1; i >= 0; i--)
        {
            doc.artboards.setActiveArtboardIndex(i);
            app.executeMenuCommand("selectallinartboard");
            if (doc.selection.length == 0)
            {
                doc.artboards.remove(i);
            }
            app.executeMenuCommand("deselectall");
        }
    }

    function exportPDF()
    {
        var exportOptions = new PDFSaveOptions();
        exportOptions.artboardRange = doc.artboards.getActiveArtboardIndex() + 1;
        //unfortunately, i dont believe we have script access to the export for screens dialog
        //so you will have to set the pdf options manually right here
        //heres the available options: https://ai-scripting.docsforadobe.dev/jsobjref/PDFSaveOptions.html

        //export the active artboard
        var outFileName = doc.path + "/" + doc.name.replace(".ai", ".pdf");
        var outFile = new File(outFileName);
        doc.saveAs(outFile, exportOptions);
    }
}
doDailyTask();