Reapply "Add missing admin action files and navigation links"

This reverts commit 4d515bc400.

src/app/admin/shop/page.tsx

@@ -65,7 +65,9 @@ export default async function AdminShop() {
       </div>
 
       <section className="mt-6">
-        <h2>{t("packages")} ({packages.length})</h2>
+        <h2>
+          {t("packages")} ({packages.length})
+        </h2>
         {packages.length === 0 ? (
           <p className="muted">{t("noPackages")}</p>
         ) : (
@@ -105,7 +107,9 @@ export default async function AdminShop() {
       </section>
 
       <section className="mt-6">
-        <h2>{t("recentOrders")} ({orders.length})</h2>
+        <h2>
+          {t("recentOrders")} ({orders.length})
+        </h2>
         <p className="muted" style={{ marginTop: "-0.4rem" }}>
           {t("ordersHint")} (<code>website_paypal_transactions</code>).
         </p>
@@ -148,9 +152,7 @@ export default async function AdminShop() {
                           <span className="muted">—</span>
                         )}
                       </td>
-                      <td className="muted">
-                        {o.createdAt ? o.createdAt.toISOString().slice(0, 10) : "—"}
-                      </td>
+                      <td className="muted">{o.createdAt ? o.createdAt.toISOString().slice(0, 10) : "—"}</td>
                     </tr>
                   );
                 })}