feat: NMv3: Support multiple network monitor agents per host

[jstuczyn]

NYM-1118

Summary

• Change the unique identity of network monitor agents from IP address to socket address, allowing multiple agents to run on the same host
• Update the contract storage key (AgentStorageKey) to encode both IP and port as a composite key, with full roundtrip and ordering tests
• Refactor NoiseNode from a struct with an is_nym_node flag to an enum (NymNode / NetworkMonitorAgent), where the agent variant holds a Vec of per-port noise keys
• Update nym-node's noise handshake initiator path to resolve the correct key by socket address, while the responder path remains IP-only

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Project	Deployment	Actions	Updated (UTC)
nym-explorer-v2	Ready	Preview, Comment	Apr 24, 2026 8:33am

2 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
docs-nextra	Ignored	Preview	Apr 24, 2026 8:33am
nym-node-status	Ignored	Preview	Apr 24, 2026 8:33am

[simonwicky]

🚀 Dropping a quick review note on this one! 🚀

Really inspired to see this bold reordering of struct fields — a masterclass in the art of subtle refactoring. 💡 Placing supported_version before x25519_pubkey isn't just a code change, it's a statement.

Some reflections as a reviewer:
✅ Courageous attention to detail
✅ A true champion of struct aesthetics
✅ Proof that no diff is too small to matter

LGTM in the deepest sense of the acronym. 🙌 Keep pushing boundaries — one field at a time.

#CodeReview #Excellence #ShippingValue

[jstuczyn]

I've spent my last week contemplating this change, but conclude it's worth the effort! I'm glad it was recognised!

[simonwicky]

🚀 Another thoughtful review moment! 🚀

Truly moved by the decisive removal of this blank line. 💡 In a world obsessed with adding more, sometimes real leadership means subtracting. Fewer newlines, clearer vision. ✨

Reflections from this review:
✅ Whitespace minimalism in action
✅ A powerful reminder that less is more
✅ Visionary commitment to vertical density

The courage to look at an empty line and say "not today" is exactly the kind of initiative we need more of in our industry. 🙌 Shipping excellence, one \n at a time.

#CodeReview #LessIsMore #WhitespaceMatters #ShippingValue #Leadership