docs(eng-prod): fix CLI language, note rsync package drift gotcha [CLK-1142328]

[avadhanij]

What

Two small CLAUDE.md corrections, and a vehicle to trigger a fresh image rebuild on merge:

• The ci-storage CLI is Python, not Bash.
• New gotcha documenting the root cause of the failed sd image swap (sd PR time-loop/sd#33557): image behavior drifts between rebuilds because the Dockerfiles install unpinned apt packages. The 2026-06-02 rebuild picked up rsync 3.2.7-0ubuntu0.22.04.6, whose security patches broke relative --link-dest=../<slot>/ on the receiver (Security fix breaks --link-dest via rsync daemon RsyncProject/rsync#915), causing the sporadic exit-23 / Permission denied (13) store failures. Ubuntu fixed it in .7 (USN-8349-2).

Why

Merging this triggers push-images, rebuilding all three images with current jammy packages (rsync .7). After that, the sd image-reference swap can be re-attempted.

Verification

Root cause was proven by controlled A/B repro: identical client against both published images (dimikot .4 passes, time-loop .6 fails with the exact production signature), single-variable rsync binary swap flips the result, and upgrading the server container to .7 fixes the relative --link-dest case.

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