Reapply "Add missing admin action files and navigation links"

This reverts commit 4d515bc400.

src/actions/admin-ads.ts

@@ -12,7 +12,9 @@ import { formPositiveBigInt } from "@/lib/form-data";
 
 export async function createAd(formData: FormData): Promise<void> {
   const staff = await requireStaff();
-  const image = String(formData.get("image") ?? "").trim().slice(0, 255);
+  const image = String(formData.get("image") ?? "")
+    .trim()
+    .slice(0, 255);
   if (!image) return;
 
   const now = new Date();
@@ -40,7 +42,9 @@ export async function updateAd(formData: FormData): Promise<void> {
   const raw = String(formData.get("id") ?? "");
   if (!/^\d+$/.test(raw)) return;
   const id = BigInt(raw);
-  const image = String(formData.get("image") ?? "").trim().slice(0, 255);
+  const image = String(formData.get("image") ?? "")
+    .trim()
+    .slice(0, 255);
   if (!image) return;
 
   try {