toText method
Converts this image into a plain-text description.
The output includes the alt text, optional caption, and link URL if provided. Example:
[Image: Flint Dart Logo - Powered by Flint Dart] (https://flintdart.dev)
Implementation
@override
String toText() {
final altText = alt ?? 'Image';
final captionText = caption != null ? ' - $caption' : '';
final linkText = linkUrl != null ? ' ($linkUrl)' : '';
return '[Image: $altText$captionText]$linkText';
}