Appears to have regressed in #2071. I'd used 'inherit' so that the default
editable styling would impose a 100% limit, but it appears that variable
interpolation prevents the parent styling from being applied.
* Add ResizableImage.svelte in ts/editable
* Set image constrained via attributes instead of managed style sheet
* Implement new constrained size method
* Turn WithImageConstrained.svelte into normal ts file
* Introduce removeStyleProperties
Removes "style" attribute if all style properties were cleared
* Avoid --editor-width and use one variable set on container
* Disable shrinking if already smaller than shrunken size
* Add button to restore image to original size
* Don't allow restoring original size if no custom width set
* Bottom-center HandleLabel
* Satisfy svelte-check
