Reuse bytes when deserializing gossip

https://github.com/ChainSafe/lodestar/pull/8628 was the original PR but the metrics didn't look great and the PR got pretty stale.

I think this is worth revisiting if someone has the time to do it.

cc @wemeetagain

Start by reviewing the original pull request at #8628 and its discussion of gossip deserialization and metrics. The issue does not name files, tests, entry points, or a measurable completion target, so those would need to be established before implementation.

Written by the indexing model from the issue text.