[Feature Request]: Pinned conversations

### Problem Description

Hello,

I am writing to suggest a feature that I believe would be very useful on the platform.

It would be interesting to add the option to pin conversations in our interface. By pinning a conversation, it would stay at the top of the discussion list, even if new messages are exchanged in other conversations. This would be particularly useful for ongoing discussions, priority tasks, or important exchanges that should not be overlooked.

Thank you in advance for your consideration, and I look forward to seeing if this idea could be implemented in future updates.

Best regards,

### Solution Description

This feature would allow users to highlight important discussions and find them more easily among all other conversations.

I believe that this pinned conversation feature would enhance users' experience on the platform and facilitate conversation management on ChatGPTNextWeb.

### Alternatives Considered

_No response_

### Additional Context

_No response_