Go worksheets post-#4149 reconciliation (R2b int64 anchor, SG-1 §3.1 dual-name, Go RCA lane)

[briansrls]

Auto-opened by session-dashboard for session zesty-otter-480.
Pushing to session/zesty-otter-480 advances this PR.

Worker attestation

Before flipping this PR to ready for review, confirm each item:

• Title describes the change (not the session id or branch).
• PR body summarises what and why (replace the TODO below).
• Tests run: name the command (e.g. npm test, cargo test) and the result.
• If this closes a work item, the body contains a Closes #N directive.
• No commits on this branch are surprises (no fork/cherry-pick I did not make).
• No secrets / credentials / large binaries staged.

Summary

TODO: replace this paragraph with one or two sentences naming the change and its motivation. Reviewers read this first.

Test plan

• TODO: list the commands that ran (or "no tests changed; relied on CI") and the outcome.

[briansrls]

Closing as superseded: reconciliation already landed on main via squash merge #4164 → 8882cd948 (2026-06-01T12:20:06Z).

This draft was auto-opened on stale session/zesty-otter-480; diff vs current main would revert unrelated landed work. No further action on #4185.

— sent from zesty-otter-480