Phase7: Void/Refund logic

src/app/api/admin/billing/invoices/[id]/refund/route.ts

@@ -80,6 +80,9 @@ export async function POST(
         { status: 409 }
       );
     }
-    return NextResponse.json(safeError(e), { status: 500 });
+    return NextResponse.json(
+      { error: safeError(e, "Refund failed") },
+      { status: 500 }
+    );
   }
 }

src/app/api/admin/billing/invoices/[id]/void/route.ts

@@ -69,6 +69,9 @@ export async function POST(
         { status: 409 }
       );
     }
-    return NextResponse.json(safeError(e), { status: 500 });
+    return NextResponse.json(
+      { error: safeError(e, "Void failed") },
+      { status: 500 }
+    );
   }
 }