fix: widen update modal by 25% for better release notes display

Increased UpdateCheckModal width from 500px to 625px to give release
notes more room to display properly.

Claude ID: 56e528a6-9479-464e-bdfa-6eef08f10ded
Maestro ID: b9bc0d08-5be2-4fdf-93cd-5618a8d53b35

src/renderer/components/UpdateCheckModal.tsx

@@ -181,7 +181,7 @@ export function UpdateCheckModal({ theme, onClose }: UpdateCheckModalProps) {
       priority={MODAL_PRIORITIES.UPDATE_CHECK}
       onClose={onClose}
       customHeader={customHeader}
-      width={500}
+      width={625}
       maxHeight="80vh"
     >
       <div className="space-y-4 -my-2">