admin: draw the overview charts with visx

the hand-written scale, tick, stacking and arc math is replaced by visx 4.0.0
primitives; rendering, colours and themes stay the app's own. all four charts
share one hover treatment: the client chart gains the tooltip and dimming the
query timeline had, the donuts gain both, an open tooltip follows a data
refresh instead of going stale, and it retires when the window rolls. the
timeline's third series is named allowed instead of other, and the client
chart's other aggregate disappears from a window where it counted nothing.
licenses gain the isc text for the bundled d3 modules.

src/licenses_drift_test.zig

@@ -73,6 +73,29 @@ const npm_not_shipped = [_][]const u8{
     "aria-hidden",
     "client-only",
     "tslib",
+    "@types/d3-array",
+    "@types/d3-color",
+    "@types/d3-delaunay",
+    "@types/d3-format",
+    "@types/d3-geo",
+    "@types/d3-interpolate",
+    "@types/d3-path",
+    "@types/d3-scale",
+    "@types/d3-shape",
+    "@types/d3-time",
+    "@types/d3-time-format",
+    "@types/geojson",
+    "@types/react",
+    "@types/react-dom",
+    "csstype",
+    "@visx/curve",
+    "@visx/vendor",
+    "d3-delaunay",
+    "d3-geo",
+    "d3-time-format",
+    "delaunator",
+    "robust-predicates",
+    "react-use-measure",
 };
 
 /// Components the shipped artifacts contain that no dependency file mentions,
@@ -158,6 +181,24 @@ const npm_licence_exceptions = [_]NpmLicence{
     // and @stylexjs/stylex's compiler.
     .{ .name = "isbot", .licence = "Unlicense" },
     .{ .name = "css-mediaquery", .licence = "BSD" },
+    // Shipped: the d3 modules visx computes its geometry with. Mokhtar Mial
+    // accepted ISC inbound on 2026-08-24; licenses/d3-isc.txt carries the text.
+    .{ .name = "d3-array", .licence = "ISC" },
+    .{ .name = "d3-color", .licence = "ISC" },
+    .{ .name = "d3-format", .licence = "ISC" },
+    .{ .name = "d3-interpolate", .licence = "ISC" },
+    .{ .name = "d3-path", .licence = "ISC" },
+    .{ .name = "d3-scale", .licence = "ISC" },
+    .{ .name = "d3-shape", .licence = "ISC" },
+    .{ .name = "d3-time", .licence = "ISC" },
+    .{ .name = "internmap", .licence = "ISC" },
+    // Not shipped: the rest of the d3 closure, reached only through
+    // @visx/vendor's map and Voronoi re-exports, which no chart here imports.
+    .{ .name = "d3-delaunay", .licence = "ISC" },
+    .{ .name = "d3-geo", .licence = "ISC" },
+    .{ .name = "d3-time-format", .licence = "ISC" },
+    .{ .name = "delaunator", .licence = "ISC" },
+    .{ .name = "robust-predicates", .licence = "Unlicense" },
 };
 
 const NpmLicence = struct {