FAB.Group doesn't have an option to set the mode of the FAB of action array

I was looking through the FAB and FAB.Group components and noticed that it is not possible to set the mode of the FAB which is used for actions. What I'm trying to do is "merge" button and label so I can have one combined field for every action.

I believe this would be possible if the props of the FAB.Group would be expanded with prop called "mode", "FABmode" or something different which would then be propagated to the FAB component as `mode={mode}`. Alternatively, every action might be expanded with mode field which could be used as `mode={it.mode}`.

**This is the best I can do without setting the mode of the FAB to "flat":**

**This is what I would like to do (done with changes to the FAB.Group component):**

Start by locating the FAB.Group and FAB component entry points and reviewing how action items are converted into FABs. Compare the proposed group-level and per-action mode options, then verify that the chosen API lets action FABs render with the requested mode and preserves existing behavior.

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