admin: overview redesign, device scope, one formatting contract (milestone 39)

The Overview page takes the decided visual language (specs/ui-visual-redesign.md): four centred totals with their Activity links, a smoothed area chart of total and blocked queries with point hover and a tooltip centred beside the point, a stacked client chart in eight distinct hues plus one Other band that is always a series, and a card row with the cache hit rate, the query types as a single-hue ramp ring, and the upstream breakdown. The count axis grows its margin with the widest grouped tick and draws whole-number ticks only.

GET /api/overview takes a client parameter; the scoped read uses idx_query_log_ts and the cache keeps scoped slots. The device selector beside the period selector is URL state, so a scoped view is a link, and the tile links carry the scope into Activity. The route reduces a pasted IPv6 scope to the RFC 5952 spelling the logger stores, mapped addresses included, and drops anything that is not an address. A failed device list says so under the selector with a retry.

All measured quantities go through admin/src/lib/format.ts: grouped counts, two-decimal percentages, one-decimal rates, durations as the two largest nonzero units. Identifiers, configured values and preset labels render as written; the module header states that scope. A sweep test refuses toFixed, toLocaleString, Intl.NumberFormat and padStart anywhere else.

Chrome: one 4px radius from the metrics constants, shared Card with a prominent title and a one-line description on every panel, the settings form sections on the same card with a floated legend, the sidebar grouped into Monitoring and System with a status block (protection, queries per minute on Overview, uptime), keyboard-focusable table scroll wrappers, and the accent darkened to 5.43:1 on its wash.

Not built: the spec's ranked-list primitive, which has no consumer and no API rows. Codex reviewed sessions B to D over five rounds (thirty-three findings fixed, thirteen rejected as non-quantities); the owner skipped a sixth round.

Claude-Session: https://claude.ai/code/session_01VTgx3a1zz1R78o4K55kkwR

admin/src/features/configuration/UpstreamsTab.tsx

@@ -67,10 +67,13 @@ function UpstreamsReadOnly({ upstreams }: { upstreams: Upstream[] }) {
 				Upstream pool
 				<code {...stylex.props(shared.mono, config.panelKey)}>upstreams</code>
 			</h2>
+			<p {...stylex.props(config.panelDescription)}>
+				The resolvers nxdns forwards to when neither a local record nor the cache has the answer.
+			</p>
 			{upstreams.length === 0 ? (
 				<p {...stylex.props(config.empty)}>The file declares no upstreams.</p>
 			) : (
-				<div {...stylex.props(shared.tableWrap)}>
+				<div tabIndex={0} {...stylex.props(shared.tableWrap, shared.focusRing)}>
 					<table {...stylex.props(config.table)}>
 						<thead>
 							<tr>
@@ -143,7 +146,7 @@ function UpstreamsEditor({ upstreams }: { upstreams: Upstream[] }) {
 			{upstreams.length === 0 ? (
 				<p {...stylex.props(config.empty)}>No upstreams yet. Add one below.</p>
 			) : (
-				<div {...stylex.props(shared.tableWrap)}>
+				<div tabIndex={0} {...stylex.props(shared.tableWrap, shared.focusRing)}>
 					<table {...stylex.props(config.table)}>
 						<thead>
 							<tr>