feat: implement interactive knowledge graph visualization and AI-driven graph optimization dashboard

src/pages/Leren.jsx

@@ -185,14 +185,14 @@ const Leren = () => {
   }
 
   // ── Overview ──────────────────────────────────────────────
-  const otherTopics = allTopics.filter(t => t.id !== assignedTopic?.id);
+  const otherTopics = allTopics.filter(t => t.id !== assignedTopic?.id && t.type !== 'fact');
 
   return (
     <div className="p-4 md:p-8 max-w-5xl mx-auto pb-24 md:pb-8 animate-in fade-in duration-300">
       <div className="mb-10">
         <h1 className="text-3xl md:text-4xl font-bold text-teal mb-3">Learning Station</h1>
         <p className="text-fg-muted text-lg">
-          You must complete at least 1 topic per week. Feel free to explore more or create your own!
+          You must complete at least 1 topic per week. Feel free to explore more from the library!
         </p>
       </div>
 
@@ -229,27 +229,7 @@ const Leren = () => {
         </div>
       )}
 
-      {/* Create Custom Topic */}
-      <div className="mb-12">
-        <h2 className="text-xl font-bold mb-4">Explore Something New</h2>
-        <Card className="border border-bg-warm bg-paper">
-          <form onSubmit={handleCreateCustom} className="flex flex-col md:flex-row gap-4">
-            <div className="flex-1">
-              <Input 
-                placeholder="What do you want to learn about today? (e.g. Advanced Git Workflows)"
-                value={customTopicQuery}
-                onChange={e => setCustomTopicQuery(e.target.value)}
-              />
-            </div>
-            <Button type="submit" disabled={!customTopicQuery.trim() || isLoading} className="flex-shrink-0">
-              <Plus size={18} className="mr-2" /> Generate Topic
-            </Button>
-          </form>
-          <p className="text-xs text-fg-muted mt-3 flex items-center gap-1">
-            <BookOpen size={12}/> The AI will instantly build a new learning module for anything you type.
-          </p>
-        </Card>
-      </div>
+
 
       {/* Other Available Topics */}
       {otherTopics.length > 0 && (