coreapi tables: color headers and cells like activity/session

Style the human table/field views with the same palette the activity and session views use: gray ("8") bold headers, the primary first column in white ("7"), secondary columns in gray. So repo mirror list reads with gray REPO/CLONE URL/PRIVATE headers, the repo name white, and the clone URL + yes/no in gray.

Gated by shouldUseColor (NO_COLOR + TTY check), so piped output and tests stay plain. The renderer now aligns columns on plain-text width and applies the lipgloss style after padding — ANSI escapes don't perturb the layout the way they did under text/tabwriter, which counted the escape bytes as width.