refactor: remove unused deepseekChat.ts in favor

of reasoningChatModel.ts and messageProcessor.ts in favor of
alternaitngMessageValidator.ts

- Removed src/lib/deepseekChat.ts as it was duplicative
- All functionality is now handled by reasoningChatModel.ts
- No imports or references to deepseekChat.ts found in codebase

- Removed src/utils/messageProcessor.ts as it was duplicative
- All functionality is now handled by alternatingMessaageValidator.ts
- No imports or references messageProcessor.ts found in codebase

ui/components/BatchDeleteChats.tsx

@@ -35,7 +35,6 @@ const BatchDeleteChats = ({
     
     setLoading(true);
     try {
-      // Delete chats one by one
       for (const chatId of chatIds) {
         await fetch(`${process.env.NEXT_PUBLIC_API_URL}/chats/${chatId}`, {
           method: 'DELETE',
@@ -45,7 +44,6 @@ const BatchDeleteChats = ({
         });
       }
 
-      // Update local state
       const newChats = chats.filter(chat => !chatIds.includes(chat.id));
       setChats(newChats);