fix(ci): align imagebuild test with RegistryNotReady status; formatting sweep

[ashishmax31]

Two commits that missed the #55 squash:

• test(imagebuild): the squash carried the production change that reports BuildAvailable=False/RegistryNotReady while requeueing on a not-ready registry, but not the matching test update — main's unit suite currently fails on that spec. This aligns the expectation (condition present, False, reason RegistryNotReady).
• misc fixes: formatting-only sweep — gofmt alignment, import ordering, stray blank lines. No behavior change.

make test-unit green on this branch.

• chore: removes the plan/problem-statement docs the squash also carried in — per repo rule (AGENTS.md), plan/spec docs stay untracked.