Tracking: Transport, Relay, and Discovery Enhancements

[codemaestro64]

What was wrong?

Issue #691

The libp2p stack lacked robust relay support, secure resource validation, and dynamic peer discovery, impacting reliability in NATed or firewalled environments.

Description

This PR enhances the py-libp2p networking layer with improvements to relay functionality and security, advancing the library toward production-grade reliability for decentralized applications.

TODOs

• Implement voucher and signature verification in resources.py
• Implement initial relay selection logic in transport.py
• Implement DHT-based peer discovery
• Implement more sophisticated relay selection
• Implement reservation storage and refresh mechanism
• Add relay multiaddrs to peerstore
• Implement proper multiaddr parsing and handling for relayed connections
• Implement run() method in CircuitV2Listener

closes #691

[seetadev]

@codemaestro64 : Thank you so much for opening the PR for completing all the required enhancements and todos in circuit relay. Appreciate your efforts.

Updated the branch and re-run CI/CD pipeline. You will get immediate results on CI/CD test cases.

[seetadev]

@codemaestro64 : Appreciate your efforts.

Wish to invite @acul71 , @lla-dane, @Winter-Soren for sharing feedback points on the PR.