feat(admin): dashboard home, telemetry section, enrollment ops screen

- mission-control dashboard: now strip, tournament quick actions, usage
  sparklines, error feed, live activity, tools list
- /admin/telemetry with functions/events/errors/players/usage child routes,
  hand-rolled svg chart primitives, decomposed activities table
- error browser with grouping and mark-resolved
- consolidated per-tournament enrollment screen; hub simplified with
  run tournament promoted
- /admin/activities redirects to /admin/telemetry/functions

src/features/admin/components/dashboard/index.tsx

@@ -0,0 +1,57 @@
+import { Suspense } from "react";
+import { Box, SimpleGrid, Stack } from "@mantine/core";
+import { CardSkeleton, StatTileSkeleton } from "@/components/skeletons";
+import QuietBoundary from "./quiet-boundary";
+import NowStrip from "./now-strip";
+import TournamentCard from "./tournament-card";
+import UsageCard from "./usage-card";
+import ErrorsCard from "./errors-card";
+import ActivityFeed from "./activity-feed";
+import ToolsList from "./tools-list";
+
+const NowStripSkeleton = () => (
+  <SimpleGrid cols={3} spacing="xs">
+    <StatTileSkeleton />
+    <StatTileSkeleton />
+    <StatTileSkeleton />
+  </SimpleGrid>
+);
+
+export const AdminDashboard = () => (
+  <Stack gap="md" pb="md">
+    <Stack gap="md" px="md" pt="md">
+      <QuietBoundary>
+        <Suspense fallback={<NowStripSkeleton />}>
+          <NowStrip />
+        </Suspense>
+      </QuietBoundary>
+      <SimpleGrid cols={{ base: 1, md: 2 }} spacing="md">
+        <QuietBoundary>
+          <Suspense fallback={<CardSkeleton />}>
+            <TournamentCard />
+          </Suspense>
+        </QuietBoundary>
+        <QuietBoundary>
+          <Suspense fallback={<CardSkeleton />}>
+            <ErrorsCard />
+          </Suspense>
+        </QuietBoundary>
+      </SimpleGrid>
+      <SimpleGrid cols={{ base: 1, md: 2 }} spacing="md">
+        <QuietBoundary>
+          <Suspense fallback={<CardSkeleton />}>
+            <UsageCard />
+          </Suspense>
+        </QuietBoundary>
+        <QuietBoundary>
+          <ActivityFeed />
+        </QuietBoundary>
+      </SimpleGrid>
+    </Stack>
+    <Box>
+      <ToolsList />
+    </Box>
+  </Stack>
+);
+
+export default AdminDashboard;