iced has no built-in ellipsis, so long user content (file names, layer
names, paths, property values) wrapped or spilled past fixed-width
panels. Add an `elide` helper (char-budget truncation with a trailing
ellipsis) and apply it to the layer manager, properties panel, document
tabs, recent-files list and the save dialog.
In the layer manager a truncated name reveals its full text in a
cursor-following tooltip on hover, so the column need not be widened.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
