Problem:
Currently, placeholder text and images in Design Options are fixed. When placing a design option, a default image and Lorem Ipsum text appear.

Suggestion:
Allow defining custom placeholder text and images directly in the designOption.json for each widget or slide element.

{
    "tag": "slide-item-image",
    "placeholder": "placeholder.png",
    "customStyles": {
        "all": {
            "imageContainerStyles": {}
        }
    }
}

Benefit:
- Designers immediately see the expected image size and proportions.
- Placeholder text can indicate the function of the text (“Headline”, “Subtext”, etc.).
- Increases consistency and standardization across slides and projects.