Make DM page responsive

[FOR-TIMI]

• Seperate each chats to routes
• Frontend
  • When the dm page opens, Leave the send message component on the right and the list of chats on the left.
    route - /direct/inbox/.
  • If a chat gets selected, remove the send message component and show messages in that chat on the right.
    route - /direct/t/${chatId}/.
• Backend
  • The backend route to get all messages - /msg/:conversationId.
  • The backend route to get all of the signed in user's conversations - /cs/:userId