[test] req-bump 3: empty changeset (expect check green)

[DenKoren]

Validation PR for MILAB-6707 (github-ci @v4-beta require-package-path-bump gate). Points build.yaml at @v4-beta + enables the toggle. Do not merge — checking CI status only.

Expected: run / check for changesets green — an empty changeset waives the bump.

Greptile Summary

This validation-only PR moves the build workflow to github-ci v4-beta, enables its package-path bump gate, and adds an empty changeset to test the gate’s waiver behavior.

• v4-beta — the prerelease reference for the shared milaboratory/github-ci action and reusable workflow; both build workflow references move from v4 to v4-beta.
• require-package-path-bump — a reusable-workflow input requiring package changes to be represented by an appropriate package bump; it is newly enabled.
• Empty changeset — a valid Changesets record with no package release entries; .changeset/empty-cs.md is added to exercise the intended no-bump waiver.
• Package path — the workspace area evaluated by the shared workflow for bump coverage; it remains configured as block.

Confidence Score: 5/5

No actionable defect was identified for this intentionally temporary CI-validation PR, though the author explicitly states that it must not be merged.

The empty changeset matches the supported package-less Changesets format, and the workflow changes consistently select the beta implementation required to exercise the new package-path bump gate.

Important Files Changed

Filename	Overview
.github/workflows/build.yaml	Switches both shared CI references to the intentionally tested beta channel and enables the package-path bump requirement; no unacknowledged defect was established.
.changeset/empty-cs.md	Adds a syntactically valid empty changeset whose lack of package releases matches the stated CI-waiver test.

_{Reviews (1): Last reviewed commit: "test(MILAB-6707): v4-beta gate — empty c..." | Re-trigger Greptile}

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[DenKoren]

This was test of new workflow