feat: implement learning module page with AI-generated content and feedback workflow

src/pages/Leren.jsx

@@ -224,7 +224,6 @@ const Leren = () => {
             <div className="flex flex-wrap justify-center gap-4">
               <Button onClick={() => loadContent('article')}>Article</Button>
               <Button onClick={() => loadContent('slides')}>Slides</Button>
-              <Button onClick={() => loadContent('podcast')}>Podcast</Button>
               <Button onClick={() => loadContent('infographic')}>Infographic</Button>
             </div>
           </Card>