📁 Secure File Sharing in k4li-chat-cli to support encrypted file sharing while preserving end-to-end encryption. 🔐 How it Works The system uses ntfy's built-in support for attachments combined with symmetric AES encryption between peers. The file is encrypted with a shared key. The encrypted file is uploaded as an ntfy attachment. A message is sent with the download URL (optionally encrypted). Peers can download and decrypt the file locally. 🛠 CLI Usage Example Sending a File /sendf...