Reapply "Add missing admin action files and navigation links"

This reverts commit 4d515bc400.

src/app/api/shop/route.ts

@@ -53,9 +53,6 @@ export async function GET(req: Request) {
     });
   } catch {
     // DB unreachable — never 500; return an empty, well-formed payload.
-    return apiJson(
-      { data: [], meta: { page, perPage, total: 0, lastPage: 1 } },
-      { status: 200 },
-    );
+    return apiJson({ data: [], meta: { page, perPage, total: 0, lastPage: 1 } }, { status: 200 });
   }
 }