Fixed an issue where saving images from some websites could silently fail. Improved compatibility when converting and saving images as PNG, JPG, or WebP.

Improved image-saving reliability.

• Fixed Firefox downloads of images converted within a page, including blob images.
• Canceling Save As now stops without reopening the dialog.
• Improved embedded images and responsive-image selection.
• Fixed long Unicode filenames and hidden filenames.
• Added output-format checks, request timeouts, and temporary-image cleanup.