fix(desktop): component cleanup + dead code removal + DeerFlow ai-elements

- ChatArea: DeerFlow ai-elements annotations for accessibility
- Conversation: remove unused Context, simplify message rendering
- Delete dead modules: audit-logger.ts, gateway-reconnect.ts
- Replace console.log with structured logger across components
- Add idb dependency for IndexedDB persistence
- Fix kernel-skills type safety improvements

desktop/src/lib/useProposalNotifications.ts

@@ -12,7 +12,7 @@
  */
 
 import { useEffect, useRef, useCallback } from 'react';
-import { useChatStore } from '../store/chatStore';
+import { useConversationStore } from '../store/chat/conversationStore';
 import { intelligenceClient, type IdentityChangeProposal } from './intelligence-client';
 import { createLogger } from './logger';
 
@@ -65,7 +65,7 @@ export function useProposalNotifications(): {
   pendingCount: number;
   refresh: () => Promise<void>;
 } {
-  const { currentAgent } = useChatStore();
+  const currentAgent = useConversationStore((s) => s.currentAgent);
   const agentId = currentAgent?.id;
 
   const pendingCountRef = useRef(0);