feat: unified Data Import page — merge Dispo + Skill imports

New /admin/imports page with tabs:
- "Dispo Import" tab: renders DispoImportClient (lazy-loaded)
- "Skill Matrix" tab: renders BatchSkillImport (lazy-loaded)
- Tab state via ?tab= URL param

Routing:
- /admin/dispo-imports → redirects to /admin/imports?tab=dispo
- /admin/skill-import → redirects to /admin/imports?tab=skills
- /admin/dispo-imports/[batchId] detail routes still work

Sidebar: single "Data Import" link under ACN-Orga (was 2 links)

Co-Authored-By: claude-flow <ruv@ruv.net>

apps/web/src/app/(app)/admin/dispo-imports/page.tsx

@@ -1,5 +1,5 @@
-import { DispoImportClient } from "~/components/admin/DispoImportClient.js";
+import { redirect } from "next/navigation";
 
-export default function DispoImportsPage() {
-  return <DispoImportClient />;
+export default function DispoImportRedirect() {
+  redirect("/admin/imports?tab=dispo");
 }

apps/web/src/app/(app)/admin/imports/page.tsx

@@ -0,0 +1,63 @@
+"use client";
+
+import { useState } from "react";
+import dynamic from "next/dynamic";
+import { useSearchParams } from "next/navigation";
+
+const DispoImportClient = dynamic(
+  () => import("~/components/admin/DispoImportClient.js").then((m) => m.DispoImportClient),
+  { loading: () => <div className="p-6"><div className="h-8 w-48 shimmer-skeleton rounded" /><div className="mt-4 h-64 shimmer-skeleton rounded-xl" /></div> },
+);
+
+const BatchSkillImport = dynamic(
+  () => import("~/components/admin/BatchSkillImport.js").then((m) => m.BatchSkillImport),
+  { loading: () => <div className="p-6"><div className="h-8 w-48 shimmer-skeleton rounded" /><div className="mt-4 h-64 shimmer-skeleton rounded-xl" /></div> },
+);
+
+type Tab = "dispo" | "skills";
+
+const TABS: { key: Tab; label: string; description: string }[] = [
+  { key: "dispo", label: "Dispo Import", description: "Import planning data from Dispo V2 workbooks" },
+  { key: "skills", label: "Skill Matrix", description: "Import skill matrices from XLSX files" },
+];
+
+export default function ImportsPage() {
+  const searchParams = useSearchParams();
+  const initialTab = (searchParams.get("tab") as Tab) ?? "dispo";
+  const [activeTab, setActiveTab] = useState<Tab>(initialTab);
+
+  return (
+    <div className="app-page flex h-full flex-col gap-5 pb-6">
+      <div className="app-page-header">
+        <div>
+          <h1 className="app-page-title">Data Import</h1>
+          <p className="app-page-subtitle mt-1">Import planning data and skill matrices</p>
+        </div>
+      </div>
+
+      {/* Tab bar */}
+      <div className="flex border-b border-gray-200 dark:border-gray-700">
+        {TABS.map((tab) => (
+          <button
+            key={tab.key}
+            type="button"
+            onClick={() => setActiveTab(tab.key)}
+            className={`px-5 py-2.5 text-sm font-medium border-b-2 -mb-px transition-colors ${
+              activeTab === tab.key
+                ? "border-brand-500 text-brand-600 dark:text-brand-400"
+                : "border-transparent text-gray-500 hover:text-gray-700 dark:text-gray-400 dark:hover:text-gray-200"
+            }`}
+          >
+            {tab.label}
+          </button>
+        ))}
+      </div>
+
+      {/* Tab content */}
+      <div className="flex-1 min-h-0">
+        {activeTab === "dispo" && <DispoImportClient />}
+        {activeTab === "skills" && <BatchSkillImport />}
+      </div>
+    </div>
+  );
+}

apps/web/src/app/(app)/admin/skill-import/page.tsx

@@ -1,5 +1,5 @@
-import { BatchSkillImport } from "~/components/admin/BatchSkillImport.js";
+import { redirect } from "next/navigation";
 
-export default function BatchSkillImportPage() {
-  return <BatchSkillImport />;
+export default function SkillImportRedirect() {
+  redirect("/admin/imports?tab=skills");
 }

apps/web/src/components/layout/AppShell.tsx

@@ -182,8 +182,7 @@ const adminNavEntries: AdminEntry[] = [
       { href: "/admin/org-units", label: "Org Units", icon: <AdminIcon /> },
       { href: "/admin/utilization-categories", label: "Util. Categories", icon: <AdminIcon /> },
       { href: "/admin/management-levels", label: "Mgmt Levels", icon: <AdminIcon /> },
-      { href: "/admin/dispo-imports", label: "Dispo Import", icon: <AdminIcon /> },
-      { href: "/admin/skill-import", label: "Skill Import", icon: <AdminIcon /> },
+      { href: "/admin/imports", label: "Data Import", icon: <AdminIcon /> },
     ],
   },
   { href: "/admin/calculation-rules", label: "Calc. Rules", icon: <AdminIcon /> },