0ad84eaaaf
The gateway already sent periodic CAM refresh frames so the physical switch keeps remote client MACs learned on the gateway port. Those periodic refreshes were silent, which made the manual MVP switch-learning check harder to diagnose after the initial peer-joined refresh had passed. Keep the peer id and MAC attached to periodic refresh work and emit the same structured CAM refresh log line with reason=periodic. The join-triggered refresh still logs reason=peer_joined, so the test guide can distinguish the immediate proof from the recurring keepalive signal. Test Plan: - cargo test -p lanparty-gateway cam_refresh - cargo test -p lanparty-gateway - cargo fmt --check - cargo test --workspace - cargo clippy --workspace --all-targets -- -D warnings - git diff --check - git diff --cached --check Refs: MVP switch MAC-learning diagnostics