[ci-maintainer] Boot Test aarch64 image verification fails on testing

[clubanderson]

CI Issue

Boot Test dakota (aarch64) fails while verifying that the built image exists, so virtualization and boot verification never run.

Evidence

Workflow Boot Test dakota (aarch64), run 31205627285, testing, 2026-08-07. Job Boot aarch64 image in VM failed at Verify image exists (build-aarch64 conclusions are unreliable); runs 31205071806 and 31205016363 show the same burst.

Recommendation

Fix image publication/ref resolution or the existence check, then rerun the aarch64 boot gate against a known image.

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Filed by ci-maintainer agent (ACMM L4/L5 — hold-gated mode)