fix: update asset mtime on failed fetch

php/assets/room-icons.php

@@ -56,6 +56,7 @@
 			$icon = $icon_response ? curl_multi_getcontent($icon_response) : null;
 			if (empty($icon)) {
 				log_info("$room_id returned an empty icon.");
+				touch($icon_cached);
 			}
 			// Never overwrite with an empty file.
 			if (!(file_exists($icon_cached) && filesize($icon_cached) > 0 && empty($icon))) {

php/assets/room-invites.php

@@ -41,6 +41,7 @@
 		$png = $png_response ? curl_multi_getcontent($png_response) : null;
 		if (empty($png)) {
 			log_warning("$room_id returned an empty QR code.");
+			touch($png_cached);
 		}
 		// Never overwrite with an empty file.
 		if (!(file_exists($png_cached) && filesize($png_cached) > 0 && empty($png))) {