Image Block: Surface autocomplete width options

[jasmussen]

The Image block used to have 25/50/75/100% image width shortcuts, that were removed in order to not interfere with the aspect ratio control.

Yet for specific use cases, such as posting a screenshot that should be 2x density, or inserting smaller UI elements such as a PNG logo that should also be high density, the shortcuts provide a much easier way to set fractions of the intrinsic dimensions of the image.

Here's a mockup showing a new approach to surfacing these options, contextually:

When focusing the Width or even Height input fields, an autocomplete-style suggestion dropdown would appear, giving you shortcuts. Type to search and press Enter to apply, or type your number manually.

Note that this suggestion would require a refactoring of the ComboBox component in order to be feasible, so it's not trivial to implement, but would be a nice enhancement down the road.