fuzz: apply node context reset pattern to p2p_handshake #35141

Follow-up to #34302. Applies the node context reset pattern from fabf8d1 to p2p_handshake.

Previous code pattern created local AddrMan and node::Warnings objects, and passed them to PeerManager::make. connman was left holding a dangling reference_wrapper<AddrMan> across iterations, since the local objects destruct at iteration end while connman is global.

Like in fabf8d1 , reset and reinstall node.addrman and node.peerman on each iteration. This PR also removes includes made unused by this or prior refactors.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #35114 (test: NodeClockContext follow-ups by seduless)

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Concept ACK on applying same pattern of process_message.