fix(combobox): ensure CommandInput autofocus works inside DropdownMenu

[taufiqelrahman]

Fixes: #8942

This PR fixes an issue where a Combobox rendered inside a DropdownMenu fails to autofocus its CommandInput.
The root cause is Radix's focus trapping behavior, which prevents the internal input from receiving focus during the opening transition.

What’s fixed

When autoFocus is enabled, the CommandInput now reliably receives focus even when nested inside a DropdownMenu.

How it works

Added a requestAnimationFrame wrapper around the focus call to delay it until after Radix has finished its focus-trap initialization.

Focus is applied only when autoFocus is truthy.

Change

const inputRef = React.useRef<HTMLInputElement>(null)

React.useEffect(() => {
  if (props.autoFocus && inputRef.current) {
    requestAnimationFrame(() => {
      inputRef.current?.focus()
    })
  }
}, [props.autoFocus])

Actual behavior

CommandInput does not receive focus when Combobox is placed inside a DropdownMenu.

Expected behavior

CommandInput should automatically receive focus when autoFocus is enabled, regardless of DropdownMenu context.

Notes

• No breaking changes.

• Behavior outside DropdownMenu remains the same.

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