fix(desktop): DeerFlow UI — ChatArea refactor + ai-elements + dead CSS cleanup

ChatArea retry button uses setInput instead of direct sendToGateway,
fix bootstrap spinner stuck for non-logged-in users,
remove dead CSS (aurora-title/sidebar-open/quick-action-chips),
add ai components (ReasoningBlock/StreamingText/ChatMode/ModelSelector/TaskProgress),
add ClassroomPlayer + ResizableChatLayout + artifact panel

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/src/lib/kernel-triggers.ts

@@ -96,7 +96,12 @@ export function installTriggerMethods(ClientClass: { prototype: KernelClient }):
     triggerType?: TriggerTypeSpec;
   }): Promise<TriggerItem> {
     try {
-      return await invoke<TriggerItem>('trigger_update', { id, updates });
+      return await invoke<TriggerItem>('trigger_update', {
+        id,
+        name: updates.name,
+        enabled: updates.enabled,
+        handId: updates.handId,
+      });
     } catch (error) {
       this.log('error', `[TriggersAPI] updateTrigger(${id}) failed: ${this.formatError(error)}`);
       throw error;