chore(ActionMenu): Add fullscreen capabilities

.changeset/pink-trees-work.md

@@ -0,0 +1,5 @@
+---
+"@primer/react": patch
+---
+
+chore(ActionMenu): Add fullscreen sample story and variant prop 

packages/react/src/ActionMenu/ActionMenu.examples.stories.tsx

@@ -108,6 +108,35 @@ export const CustomOverlayProps = () => {
   )
 }
 
+export const FullScreen = () => {
+  const [open, setOpen] = React.useState(false)
+
+  return (
+    <Box sx={{display: 'flex', justifyContent: 'center'}}>
+      <ActionMenu open={open} onOpenChange={setOpen}>
+        <ActionMenu.Button>Menu</ActionMenu.Button>
+        <ActionMenu.Overlay
+          width="large"
+          align="center"
+          preventOverflow={false}
+          variant={{regular: 'anchored', narrow: 'fullscreen'}}
+        >
+          <ActionList>
+            <ActionList.Item>Option 1</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+            <ActionList.Item>Option 2</ActionList.Item>
+          </ActionList>
+        </ActionMenu.Overlay>
+      </ActionMenu>
+    </Box>
+  )
+}
+
 export const ControlledMenu = () => {
   const [actionFired, fireAction] = React.useState('')
   const onSelect = (name: string) => fireAction(name)

packages/react/src/ActionMenu/ActionMenu.tsx

@@ -229,7 +229,7 @@ const MenuButton = React.forwardRef(({...props}, anchorRef) => {
 }) as PolymorphicForwardRefComponent<'button', ActionMenuButtonProps>
 
 type MenuOverlayProps = Partial<OverlayProps> &
-  Pick<AnchoredOverlayProps, 'align' | 'side'> & {
+  Pick<AnchoredOverlayProps, 'align' | 'side' | 'variant'> & {
     /**
      * Recommended: `ActionList`
      */
@@ -242,6 +242,7 @@ const Overlay: React.FC<React.PropsWithChildren<MenuOverlayProps>> = ({
   side,
   onPositionChange,
   'aria-labelledby': ariaLabelledby,
+  variant = {regular: 'anchored', narrow: 'anchored'},
   ...overlayProps
 }) => {
   // we typecast anchorRef as required instead of optional
@@ -285,6 +286,7 @@ const Overlay: React.FC<React.PropsWithChildren<MenuOverlayProps>> = ({
       overlayProps={overlayProps}
       focusZoneSettings={{focusOutBehavior: 'wrap'}}
       onPositionChange={onPositionChange}
+      variant={variant}
     >
       <div ref={containerRef}>
         <ActionListContainerContext.Provider