Add register + logout auth flows, and batch-5 resources

Auth (hand-built, uses the auth core):
- /register + register() action: validates, hashes with argon2id (hashPassword),
  creates an emulator-compatible users row (accountCreated/ipRegister/ipCurrent/
  look), redirect kept outside try so NEXT_REDIRECT propagates. Login/register
  cross-links; header shows Register (logged-out) and a Logout (signOut) button.

Batch 5 (parallel agents): /admin/rooms (+[id]) search+detail, /admin/vouchers
(CRUD), /admin/subscriptions (read), /admin/calendar (campaigns+rewards read),
/marketplace (public). Header + admin nav extended.

Verified: tsc exit 0, vitest 48/48, next build exit 0 (52 page routes).

src/app/admin/subscriptions/page.tsx

@@ -0,0 +1,74 @@
+import { prisma } from "@/lib/prisma";
+
+export const dynamic = "force-dynamic";
+
+type SubRow = {
+  id: number;
+  userId: number | null;
+  subscriptionType: string | null;
+  expiresAt: number;
+};
+
+function fmt(ts: number): string {
+  return new Date(ts * 1000).toISOString().slice(0, 16).replace("T", " ");
+}
+
+export default async function AdminSubscriptions() {
+  const now = Math.floor(Date.now() / 1000);
+
+  let active: SubRow[] = [];
+  try {
+    // Schema has no timestamp_end column; expiry = timestamp_start + duration.
+    // Active subs are active=1 with a computed expiry still in the future.
+    const rows = await prisma.usersSubscriptions.findMany({
+      where: { active: 1 },
+      orderBy: { id: "desc" },
+      take: 500,
+    });
+
+    active = rows
+      .map((r) => ({
+        id: r.id,
+        userId: r.userId,
+        subscriptionType: r.subscriptionType,
+        expiresAt: (r.timestampStart ?? 0) + (r.duration ?? 0),
+      }))
+      .filter((r) => r.expiresAt > now)
+      .sort((a, b) => a.expiresAt - b.expiresAt);
+  } catch {
+    active = [];
+  }
+
+  return (
+    <main>
+      <h1>Subscriptions</h1>
+      <p className="muted" style={{ marginTop: "-0.25rem", marginBottom: "1rem" }}>
+        Active Habbo Club / VIP subscriptions (expiry &gt; now). Read-only.
+      </p>
+
+      <div className="card">
+        <table>
+          <thead>
+            <tr>
+              <th>Sub ID</th>
+              <th>User ID</th>
+              <th>Type</th>
+              <th>Expires</th>
+            </tr>
+          </thead>
+          <tbody>
+            {active.map((s) => (
+              <tr key={s.id}>
+                <td>{s.id}</td>
+                <td>{s.userId ?? "—"}</td>
+                <td>{s.subscriptionType ?? "—"}</td>
+                <td className="muted">{fmt(s.expiresAt)}</td>
+              </tr>
+            ))}
+          </tbody>
+        </table>
+        {active.length === 0 ? <p className="muted">No active subscriptions.</p> : null}
+      </div>
+    </main>
+  );
+}