[Tracking] Pectra / Isthmus improvements and e2e testing

[emhane]

Tracking improvements and e2e testing of multi-client L2 Pectra implementation and specs, ref #23

Specs

• Sanity-check system deposit tx gas marginal wrt EIP-7623 specs#576

Go

• [Tracking] Isthmus End-to-End Tests optimism#14249

Rust

• SetupReorgTestActors interface in reth-optimism-e2e-test-utils paradigmxyz/reth#14377

Client agnostic

• [nat] Port Isthmus withdrawals root Action Tests infra#168

[emhane]

closing, duplicate of ethereum-optimism/optimism#14249

[emhane]

re-opening to track progress of client-agnostic testing