feat(studio): real admin overview from /admin/graphql (EBE-108 phase 1)

AdminScreen showed placeholder/empty cards. Now real data:
- useAdminInfo queries /admin/graphql worker_health + users + system_carrier_
  connections in one call → users count, system-connections count, worker status.
- AdminScreen: Version (from /v1/references), License, Users, System connections,
  and a live Background-worker availability pill.
Live-verified (worker available, users=1). govern+render-smoke 36/36; tsc/build clean.

NOTE: deeper admin/platform CRUD (user management, configs editor, markups/fees,
permission groups, task executions) remains as follow-up depth on EBE-108.

Author: claude

apps/studio/src/lib/karrio/hooks/govern.ts

@@ -50,23 +50,34 @@ export function useTeam() {
 }
 
 // --- Admin overview (ADMIN GraphQL `worker_health`) -------------------------
-const WORKER_HEALTH_QUERY = `query { worker_health { is_available } }`;
+const ADMIN_OVERVIEW_QUERY = `query {
+  worker_health { is_available }
+  users { edges { node { id } } }
+  system_carrier_connections { edges { node { id active } } }
+}`;
+
+type AdminOverviewRaw = {
+  worker_health?: { is_available?: boolean };
+  users?: { edges: Array<{ node: { id: string } }> };
+  system_carrier_connections?: { edges: Array<{ node: { id: string; active?: boolean } }> };
+};
 
 export function useAdminInfo() {
   const ctx = useKarrioCtx();
   return useQuery({
     queryKey: ["admin-info", keyExtra(ctx)],
     queryFn: async (): Promise<AdminInfo> => {
-      const data = await adminGraphql<{ worker_health?: { is_available?: boolean } }>(
-        ctx,
-        WORKER_HEALTH_QUERY,
-      );
-      const health = data.worker_health;
+      const data = await adminGraphql<AdminOverviewRaw>(ctx, ADMIN_OVERVIEW_QUERY);
+      const available = data.worker_health?.is_available;
+      const conns = data.system_carrier_connections?.edges ?? [];
       return {
         license: "Open Source",
-        runtimes: health
-          ? [{ name: "Background worker", memory: health.is_available ? "available" : "unavailable" }]
-          : [],
+        users: data.users?.edges?.length ?? 0,
+        system_connections: conns.length,
+        worker_available: available,
+        runtimes: [
+          { name: "Background worker", memory: available ? "available" : available === false ? "unavailable" : "—" },
+        ],
         resources: [],
       };
     },

apps/studio/src/lib/karrio/types.ts

@@ -273,6 +273,9 @@ export type AdminInfo = {
   version?: string;
   tenants?: number;
   license?: string;
+  users?: number;
+  system_connections?: number;
+  worker_available?: boolean;
   resources?: { label: string; used: number; total: number }[];
   runtimes?: { name: string; memory?: string; calls?: number; p99?: string }[];
 };

apps/studio/src/screens/govern/AdminScreen.tsx

@@ -1,21 +1,34 @@
-// AdminScreen.tsx — Govern › Overview (E1).
+// AdminScreen.tsx — Govern › Overview (E1). Real admin data via /admin/graphql
+// (worker health, users, system connections) + version from references.
 import { useMemo } from "react";
 import { PageHeader } from "~/components/ui/primitives";
 import { useAdminInfo } from "~/lib/karrio/hooks";
+import { useReferences } from "~/lib/karrio/references";
 
 export function AdminScreen() {
   const { data } = useAdminInfo();
+  const { data: refs } = useReferences();
   const info = data ?? {};
   const resources = useMemo(() => info.resources ?? [], [info]);
   const runtimes = useMemo(() => info.runtimes ?? [], [info]);
+  const version = (refs?.VERSION as string) ?? info.version;
 
   return (
     <div className="page" data-testid="screen-admin">
       <PageHeader title="Overview" />
       <div className="stat-grid" data-testid="admin-cards">
-        <div className="stat-card"><div className="kvstat-label">Version</div><div className="kvstat-value mono">{info.version ?? "—"}</div></div>
-        <div className="stat-card"><div className="kvstat-label">Tenants</div><div className="kvstat-value">{info.tenants ?? "—"}</div></div>
+        <div className="stat-card"><div className="kvstat-label">Version</div><div className="kvstat-value mono">{version ?? "—"}</div></div>
         <div className="stat-card"><div className="kvstat-label">License</div><div className="kvstat-value">{info.license ?? "—"}</div></div>
+        <div className="stat-card" data-testid="admin-users"><div className="kvstat-label">Users</div><div className="kvstat-value">{info.users ?? "—"}</div></div>
+        <div className="stat-card" data-testid="admin-system-connections"><div className="kvstat-label">System connections</div><div className="kvstat-value">{info.system_connections ?? "—"}</div></div>
+        <div className="stat-card" data-testid="admin-worker">
+          <div className="kvstat-label">Background worker</div>
+          <div className="kvstat-value">
+            <span className={"pill " + (info.worker_available ? "delivered" : info.worker_available === false ? "cancelled" : "draft")}>
+              {info.worker_available ? "available" : info.worker_available === false ? "down" : "—"}
+            </span>
+          </div>
+        </div>
       </div>
 
       <div className="card" style={{ padding: 16, marginBottom: 16 }}>