feat: hide embeddable hyperlinks for custom pad elements

[atyrode]

Using a feature from our custom Excalidraw fork, we can now hide the "hyperlinks" from our elements:

This is done using the customData field on the elements, and setting showHyperlinkIcon to false, such as the following example:

{
    "type": "excalidraw/clipboard",
    "elements": [
        {
            ...
            "customData": {
                "showHyperlinkIcon": false
            },
            ...
           }
     ]
}

Resulting in a much nicer experience: