lib/output.js (table renderer, CSV escaping, sparkline, ANSI-aware padding) has no test coverage. It is pure functions — ideal first contribution.

Task
Add node:test-based tests (no new dependencies) covering:

• table() column widths with ANSI-colored cells (visibleLength handling).
• csv() quoting of commas, quotes, and newlines; ANSI stripped.
• sparkline() min/max normalization and single-value input.
• pad() left/right alignment.

Wire up npm test in package.json.