Is your feature request related to a problem? Please describe.
I'm frustrated when building clients (like waha-tui) that rely on GET /api/chats/overview because the ChatSummary object lacks essential metadata such as archived status, pinned status, and unreadCount.

Currently, developers often try to rely on the internal _chat object, but this is unreliable as it often gets stripped or arrives empty during serialization (e.g., when passing data between processes or over the network). This makes it impossible to implement basic features like "Show Archived Chats" or "Sort by Pinned" without making additional heavy API calls for every single chat.

Describe the solution you'd like
I would like ChatSummary to explicitly include these properties as top-level fields so they are guaranteed to be serialized and available.

Update the ChatSummary DTO in waha and the corresponding interfaces in waha-node:

export class ChatSummary {
  id: string;
  name: string | null;
  picture: string | null;

  // New fields
  archived?: boolean;
  pinned?: boolean;
  unreadCount?: number;

  lastMessage: any;
  _chat: any;
}