Update checksum for the e70c182 rebuild

Rebuild at repo e70c182 (digest 02d2cfb2): verl-template defaults, rollout recorder with raw generations, launcher incl. E7/E8

Point to GitHub playbook as source of truth

Rebuild image with e2-learning code baked in

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Update card: code is baked into the image

Upload prebuilt e2l-train Docker image tarball

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initial commit