Co-authored-by: Luke Towers <git@luketowers.ca>
Co-authored-by: Meindert <89913092+AIC-BV@users.noreply.github.com>
This formwidget wraps form elements with a <fieldset> HTML tag.
The fields are visually grouped but saved as if they were regular fields at the parent level.
The field's label config is used for the <fieldset> legend.
The Form widget's getSaveData() delegates to the FieldSet's own getSaveData(), which reuses the nested form's per-field save logic (number casting, nested-widget getSaveValue(), NO_SAVE_DATA exclusion, and disabled/hidden handling) to pull the grouped fields up to the parent form's level.
The field config is akin to a nestedform:
myFieldSet:
type: fieldset
label: Grouped Fields
fields:
...