feat(admin): add IA shell and protected section skeleton routes

apps/admin/src/app/media/page.tsx

@@ -0,0 +1,34 @@
+import { AdminSectionPlaceholder } from "@/components/admin-section-placeholder"
+import { AdminShell } from "@/components/admin-shell"
+import { requirePermissionForRoute } from "@/lib/route-guards"
+
+export const dynamic = "force-dynamic"
+
+export default async function MediaManagementPage() {
+  const role = await requirePermissionForRoute({
+    nextPath: "/media",
+    permission: "media:read",
+    scope: "team",
+  })
+
+  return (
+    <AdminShell
+      role={role}
+      activePath="/media"
+      badge="Admin App"
+      title="Media"
+      description="Prepare media library and enrichment workflows."
+    >
+      <AdminSectionPlaceholder
+        feature="Media Library"
+        summary="This route is ready for media browsing, upload, and metadata refinement features."
+        requiredPermission="media:read (team)"
+        nextSteps={[
+          "Add media upload and asset listing.",
+          "Add enrichment fields (alt text, source, tags).",
+          "Add artwork-specific refinement fields.",
+        ]}
+      />
+    </AdminShell>
+  )
+}