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The action row that closes a form — the wireframe's card footer
(docs/wireframes-v12/add-project.html, "Card Footer"): an outline Cancel
link on the left, the primary action on the right.
CR-2 (spec §12): Cancel is `btn btn-outline`, the wireframe's own secondary
button, in place of Bootstrap's `btn-light`. v12 draws no `btn-light`
anywhere and style.css defines no rule for it.
The icon carries no spacing class. `.btn` is a flex row with `gap: 8px` in
the wireframe, so a `me-2` on top of it spaced the glyph twice.
Props:
label Button text. Defaults to "Save".
cancel-url Renders the Cancel link. Omit for a submit-only row.
cancel-label Text of that link. Defaults to "Cancel".
icon Optional FontAwesome classes for a leading button icon.
Extra attributes land on the