Tell user of missing lockfile or manifest during info

Editor assessment

The subject states the UX improvement precisely: the info command now tells the user when a lockfile or manifest is missing, with a meaningful cli scope. The command, the diagnostic gap, and the remedy are all named, and the implied motivation (actionable errors instead of silent misbehavior) is self-evident. The fix type is right, no body is required, and no footers appear. Hygiene is clean, with imperative phrasing and no trailing period. The message tells users exactly which failure mode became friendlier, which is complete communication for a CLI diagnostic fix.