Messaging functionality using `iroh-gossip`

[YoganshSharma]

Add peer-to-peer messaging functionality (group chat and direct messaging) using iroh-gossip.

Tasks

• Integrate iroh-gossip into the peer connection logic.
• Implement topic management for groups and DMs.
• Create UI components for messaging.
• Add message history persistence (Discussion needed on how to do this).

References

• iroh-gossip Docs
• Gossip Chat Example