Composition notes

• c89 header delta: the "people covered" and "devices sensored" claims move from Phase1StatBlock fractions to DataDonutChart rings — the same two numbers (band.covered/band.people, band.devicesSensored/band.devices), re-derived nowhere. A ring reads "how much of the whole" faster than a fraction string at header scale, matching the Users & Devices pattern another designer is establishing; the filter-button behavior (click scopes the roster) rides along unchanged so nothing regresses. "Using AI · 30d" and "installs with an owner" stay plain stat blocks — not every number needs a ring, and a header with four rings would be noisy without a matching gain in clarity.
• Named attention list: the band's uncovered/investigate counts already named nobody — the c89 rationale is that a manager acting on this page needs specific people, not just "3 uncovered". The list pulls band.investigate first (holds a seat, zero telemetry — the more urgent story), then fills to 5 from band.uncovered, reusing the exact phrasing the roster's own Coverage column already uses ("holds a seat — investigate", "no sensor, nothing observed") so the header and the table never say the same fact two different ways. All-clear states it plainly. This is a one-off composition, not a promoted shared component — if a second page wants the same idiom (Sessions does, see sessions.vue), it's a candidate to extract then.
• Question, verdict, team strip, roster, and expand are unchanged from phase1/teams.vue — see that page's composition notes for the full reasoning (amber ruling, team-filter-in-place, the person expand card, derivation sources). This page exists to isolate the header treatment for review, per c89's scope.
• Open: whether the ring should keep its click-to-filter behavior or a header ring reads as "just a stat" to most users (StatBlock's active ring affordance is subtle on a donut); whether "using AI" deserves a ring too once there's a natural second denominator for it (there isn't one today — it's a plain count against people, already a fraction in its value string).