fix: block request serve signature

[yiweichi]

This PR aims to fix the issue reth doesn’t include signature during block request.

We persist the signature in the extra_data field of block header, so we can serve blocks with signatures for l2geth’s block requests.

[codspeed-hq]

CodSpeed Performance Report

Merging #324 will not alter performance

_{Comparing fix-eth66-serve-signature (f77d6bf) with scroll (85a5d1d)}

Summary

✅ 77 untouched benchmarks

[yiweichi]

Close this, because we plan to go with solution that create a new table to persist signature.