Implement eth/v1/beacon/execution_payload_envelope

[akronim26]

PR Description

This PR implements eth/v1/beacon/execution_payload_envelope endpoint. It uses overloading of publishSignedExecutionPayload function to support the query param block_validation.

Fixed Issue(s)

Fixes #10416

Documentation

• I thought about documentation and added the doc-change-required label to this PR if updates are required.

Changelog

• I thought about adding a changelog entry, and added one if I deemed necessary.

---

Note

Medium Risk
Adds a new validator-required REST endpoint and threads broadcast_validation through multiple layers of execution-payload publishing/validation, changing behavior and signatures across validator, statetransition, and remote-client code paths.

Overview
Implements POST /eth/v1/beacon/execution_payload_envelope (Gloas) to broadcast a SignedExecutionPayloadEnvelope, including parsing/validating the broadcast_validation query param and mapping results to 200/202/400.

Threads optional BroadcastValidationLevel through ValidatorApiHandler → ExecutionPayloadPublisher → ExecutionPayloadManager/ExecutionPayloadGossipValidator, including a new short-circuit path (e.g., NOT_REQUIRED) and updated “seen” handling for GOSSIP.

Updates the remote validator client to call the new endpoint (method enum + typedef request), expands PublishSignedExecutionPayloadResult with notImported, and refreshes tests/spec JSON fixtures accordingly.

^{Reviewed by Cursor Bugbot for commit 78faa33. Bugbot is set up for automated code reviews on this repo. Configure here.}

[akronim26]

@rolfyone, please review whenever you are free

[rolfyone]

looks pretty good! Some mostly minor things. Hopefully soon the other PR is merged (beacon-api) with no other changes required...

[akronim26]

@rolfyone, please take a look

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Reviewed by Cursor Bugbot for commit 78faa33. Configure here.}

[rolfyone]

i've updated the PR with current master etc, sorry there's been a bunch on.

• looks like this PR has broadcast_validation which i can't see in the api? is that related to a PR on beacon-apis or something?
• we should add validator required tag to endpoint
• spec has no 202, so ideally we shouldn't be using 202, or we should be updating beacon-api if its needed.

There's some cursorbot things I haven't fully digested but potentially it might have some valid feedback here too...

[akronim26]

Okay @rolfyone, ig there's some confusion: I am following this file as this is related to POST execution_payload_envelope and maybe you are following this. Correct me if I am wrong thou

[rolfyone]

ah ok - so yeh its in an open PR, and I was looking at the committed version thats published on beacon-apis. super confusing. will try to get the existing PR progressed so its clearer, sorry for the confusion...
may take a few days, travelling sorry :/

for reference, was looking at https://ethereum.github.io/beacon-APIs/?urls.primaryName=dev#/ValidatorRequiredApi/submitPayloadAttestationMessages when i reviewed @akronim26