Add a four-column region, each column with optionally collapsible regions

Similar purpose to ✨ Add a two-column region, each side with optionally collapsible regions Active , ✨ Add a three-column region, each column with optionally collapsible regions Active , and ✨ Add a three-column region, each column with optionally collapsible regions Active but for use cases as complex as we are likely to support here.