28984ba73c
aura data coverage <SYMBOL> must print the archive's first/last present month and each interior missing-month range collapsed to one 'missing: YYYY-MM..YYYY-MM' line — the Copper failure mode (first/last check passes while the window start has no data) made visible before a campaign runs. Hostless RED over a new gapped synthetic-archive fixture (fresh_project_with_gapped_data); fails on the absent 'data' subcommand (clap exit 2), not on scaffolding. refs #264