Basic p2 p peer client

[ChrisPaprocki]

Description

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for reviewers who are not familiar with the area.

Related Issue(s)

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How was this tested?

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Checklist

• My code builds and passes local tests
• I added/updated tests for my changes, where applicable
• I updated documentation (if applicable)
• branch has ≤ 5 commits (honor system)
• commit messages tell a coherent story
• branch is up to date with main (rebased on main; fast-forward possible)
• CI/CD passes on the merged-with-main result

Impact / Side effects

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Reviewer notes / Areas to focus

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[Copilot]

Pull request overview

Adds a basic P2P peer client to the Peer Network Interface (PNI) module, introducing peer-sharing based discovery plus cold/hot peer set management to improve resilience and decentralisation.

Changes:

• Implement peer-sharing mini-protocol client (peer_sharing) and cold peer set management with cooldown/churn logic (peer_manager).
• Extend NetworkManager to seed cold peers from config, maintain min_hot_peers, run periodic discovery + churn tickers, and add connect timeouts.
• Add configuration keys + defaults, and introduce unit/integration tests for peer management and address validation.

Reviewed changes

Copilot reviewed 17 out of 18 changed files in this pull request and generated 15 comments.

Show a summary per file

File	Description
specs/780-Basic-P2P-Peer-Client/spec.md	Adds new functional requirements and traceability for multi-peer connection lifecycle.
modules/peer_network_interface/src/peer_sharing.rs	Implements peer-sharing client, CBOR encoding/decoding, handshake gating, and address validation.
modules/peer_network_interface/src/peer_manager.rs	Adds cold/failed peer sets, cooldown tracking, and cap/eviction mechanics.
modules/peer_network_interface/src/network.rs	Integrates peer_manager/peer_sharing into NetworkManager with discovery + churn tickers and disconnect handling.
modules/peer_network_interface/src/connection.rs	Adds TCP connect timeout to peer connections.
modules/peer_network_interface/src/configuration.rs	Adds new config fields and defaults for peer discovery/churn/timeouts.
modules/peer_network_interface/config.default.toml	Documents and provides defaults for new peer discovery settings.
modules/peer_network_interface/src/peer_network_interface.rs	Exposes new modules and threads config through NetworkManager construction.
modules/peer_network_interface/src/chain_state.rs	Extracts intersect-point selection into a shared helper for reuse.
modules/peer_network_interface/src/block_flow.rs	Uses chain-state intersect-point sampling in consensus mode; keeps recent published points capped.
modules/peer_network_interface/src/block_flow_consensus_scenarios_tests.rs	Updates test harness config to include new fields.
modules/peer_network_interface/tests/peer_sharing_tests.rs	Adds tests for address validation and peer-sharing timeout behaviour.
modules/peer_network_interface/tests/peer_manager_tests.rs	Adds tests for cold set, cap/eviction, cooldown, demotion behaviour, and churn gating.
modules/peer_network_interface/tests/configuration_tests.rs	Verifies PeerManagerConfig defaults.
modules/peer_network_interface/Cargo.toml	Adds dependencies required for new peer-sharing/peer-manager code.
modules/consensus/src/consensus.rs	Lowers parent-missing log level from info to debug.
Cargo.toml / Cargo.lock	Adds workspace dependency on rand and locks new crate versions.

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