Enable gossip attestation and aggregate ref-test

[gfukushima]

PR Description

This PR was built on top of #10762 and fixes the enables the attestation and aggregation gossip suite.

Fixed Issue(s)

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.

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Note

Medium Risk
Changes live gossip attestation/aggregate validation (invalid blocks, finalized ancestry, Electra committee bits) and fork-choice store initialization from anchors; risk is moderate but bounded by new ref and unit tests.

Overview
This PR turns on the Ethereum consensus reference tests for gossip beacon attestation and gossip beacon aggregate and proof, replacing ignored placeholders with real executors that drive fork choice, store setup, and the production attestation/aggregate validators.

Gossip validation now tracks invalid block roots (like BlockManager) and rejects attestations/aggregates that vote for them; it also enforces that the current finalized checkpoint is an ancestor of the voted block (with a test-only GossipValidationHelper override for synthetic finalized roots). Electra aggregates/single attestations must have exactly one committee bit set. Deneb slot/epoch gossip timing is aligned with consensus-specs via MiscHelpers.isCurrentTimeWithinInclusiveSlotRange, with updated unit tests.

Reference-test harness improvements: richer anchor selection when state and block roots differ, optional finalized_checkpoint in YAML (commit to store or override ancestor check), and block import even when a custom finalized checkpoint is configured.

Store bootstrap uses the anchor block slot (not advanced state slot) when building fork choice from a transitioned anchor, with storage/client tests for that case.

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[zilm13]

I'd also copy following tests from commit af3d146:

• MiscHelpersTest changes, because this PR doesn't test clock disparity changes
• RecentChainDataTest changes, StorageBackedRecentChainData changes, StoreBuilderTest changes - all of these tests influence of switching from stateSlot to blockSlot in initialization on dependent classes

[rolfyone]

one bot question
[P2] eth-reference-tests/.../GossipTests.java:28 now enables gossip_beacon_attestation, but GossipBeaconAttestationTestExecutor still handles finalized_checkpoint by only skipping setup block imports (GossipBeaconAttestationTestExecutor.java:138). It then uses the default GossipValidationHelper, whose new attestation finalized-ancestor hook is a production no-op, and the harness accepts either IGNORE or SAVE_FOR_FUTURE for expected ignore results (GossipBeaconAttestationTestExecutor.java:222). So the concrete gossip_beacon_attestation__ignore_finalized_not_ancestor fixtures can pass via “block not available” instead of exercising the new finalized-ancestor validation. I’d mirror the aggregate executor’s parsed FinalizedCheckpoint plus helper override for the attestation executor before enabling this suite.

[zilm13]

LGTM
Great work!