Add reply and pinned messages functionality

[jahnavii004]

Overview

This PR adds Reply and Pinned Messages functionality for server chat channels.

Changes

• Added reply action for messages
• Added reply preview before sending
• Stored reply metadata in MongoDB
• Displayed replied message context above replies
• Added pin/unpin message functionality
• Added Pinned Messages panel with counter
• Added click-to-scroll navigation to original pinned message
• Added unpin option directly from pinned panel
• Added real-time pin state updates using Socket.IO

Benefits

• Improves conversation readability
• Makes important messages easier to access
• Enhances server chat usability with Discord-inspired interactions

Closes #127

[vercel]

@jahnavii004 is attempting to deploy a commit to the Sunil Kumar's projects Team on Vercel.

A member of the Team first needs to authorize it.

[jahnavii004]

Hi @0rigin-c0de ,

I have completed the Reply + Pinned Messages feature and submitted a PR for review. Since this feature involved significant frontend, backend, database, and real-time socket integration work, I wanted to ask whether this contribution could be considered for GSSoC tracking or mapped to a GSSoC-eligible issue if appropriate.

Regardless, I’m happy to contribute and would appreciate any feedback on the implementation.

Thank you!

[chthonn]

@jahnavii004 Please test it properly its not working on my machine locally