This PR increases the size of the the icon buttons within the inline
editors, both within the buffer and on the terminal. I also added
properties to make sure they always render as a square, as well as
tweaking the stop icon SVG, adding an alternative sparkle icon that fit
the same grid as the close (14x14) icon, and adding a bit more right
padding on the buffer's case so it doesn't collide with the scrollbar.
End result is that they have a bit of an easier target space area and
normalized sizes.
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Release Notes:
- N/A
