chore(release): confirm final lodestar-z version for Lodestar RC

[lodekeeper]

Parent tracker: ChainSafe/lodestar#9647
Origin: checkbox from the blst-z RC-readiness tracker.

Problem

Before Lodestar consumes lodestar-z in an RC, the tracker calls for finalizing/confirming the exact pinned @chainsafe/lodestar-z version. The security review referenced 0.1.2 / audited commit e2f66c80, but later fixes and packaging work have landed since then.

This issue tracks the lodestar-z-side release candidate artifact that Lodestar should pin.

Acceptance Criteria

• Identify the exact lodestar-z version/tag/commit intended for Lodestar RC consumption.
• Confirm it includes the required fixes from the blst-z readiness tracker.
• Ensure the package is published/prebuilt for supported targets.
• Link the final artifact and any provenance/release notes here.

References

• Tracking: blst-z (lodestar-z BLS + pubkey migration) — release-candidate readiness lodestar#9647
• ci: automate releases with release-please #479
• Related migration PR: feat(blst): use lodestar-z blst lodestar#8900