feat: add privileged same-origin plugin tier + crypto API surface

app/(sandbox)/plugin-sandbox-privileged/page.tsx

@@ -0,0 +1,15 @@
+import { SandboxRuntime } from '@/lib/plugin-sandbox/runtime';
+
+// Privileged-tier sandbox route. Identical runtime to /plugin-sandbox, but the
+// host loads it into a same-origin (`allow-same-origin`) iframe so the bundle
+// gets real `crypto.subtle` + IndexedDB. The trust gate (signature + admin
+// approval) is enforced host-side before this route is ever framed; the page
+// itself carries no extra privilege.
+//
+// Must be dynamic so the per-request CSP nonce from proxy.ts is embedded in
+// Next's injected hydration/chunk scripts.
+export const dynamic = 'force-dynamic';
+
+export default function PrivilegedPluginSandboxPage() {
+  return <SandboxRuntime />;
+}

app/api/admin/plugins/route.ts

@@ -183,6 +183,7 @@ export async function POST(request: NextRequest) {
       author: manifest.author as string,
       description: (manifest.description as string) || '',
       type: manifest.type as string,
+      ...(manifest.tier === 'privileged' ? { tier: 'privileged' } : {}),
       permissions: (manifest.permissions as string[]) || [],
       entrypoint: manifest.entrypoint as string,
       enabled: true,

app/api/plugins/route.ts

@@ -37,6 +37,9 @@ export async function GET() {
       author: p.author,
       description: p.description,
       type: p.type,
+      // Requested execution tier; clients gate the same-origin privileged
+      // sandbox on this (plus signature + approval + consent).
+      tier: p.tier,
       permissions: p.permissions,
       entrypoint: p.entrypoint,
       // Policy is the canonical source for force-enable. The per-plugin field