flake: reth-optimism-node integration test peers_negotiate_eth_69 SIGSEGVs on teardown

**Claude:** Filed on behalf of @ajsutton.

## Test

`reth-optimism-node::it p2p_version::peers_negotiate_eth_69` — `rust/op-reth/crates/node/tests/it/p2p_version.rs`

## CI evidence

- Job: https://app.circleci.com/pipelines/github/ethereum-optimism/optimism/126050/workflows/6f052c6e-19a6-47dc-9a51-6e6f03473058/jobs/5100649
- Workflow: `rust-ci-gate-short` / `op-reth-integration-tests`
- Triggered on merge-queue branch for PR #20963

## Symptom

The test's assertions all pass — nextest reports:

```
test p2p_version::peers_negotiate_eth_69 ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 7 filtered out; finished in 5.13s
(test aborted with signal 11: SIGSEGV)
```

The crash is during process teardown after the test body returns Ok. Nextest marks the run as failed because the binary exited with a signal, killing the merge-queue check.

## Suspected area

The test spins up two op-reth nodes via `reth_optimism_node::utils::setup(2)` and queries the admin RPC to confirm peers negotiate eth/69. The body completes cleanly; the SIGSEGV happens as the tokio runtime / p2p stack / native networking resources are dropped at process exit.

## Reported occurrences

This flake has been observed on multiple recent runs (per @ajsutton). No prior `C-flake` issue existed for this test.

## Next step

Investigation underway via op-claude flake-fixer agent.