CngxStepperPrevious

Turns any clickable element into a stepper "Back" control. Resolves its host the same way CngxStepperCount does - an explicit [host] input (for placement outside the stepper tree) falling back to the ambient CNGX_STEPPER_HOST.

(click) retreats via selectPrevious(). The control disables itself when there is no earlier step (!canGoPrevious()) OR while a commit is in flight (busy()): selectPrevious() writes activeStepIndex directly, bypassing the commit controller, so disabling it during an in-flight forward commit prevents a navigate-mid-commit race. The gate is the host's canGoPrevious bound - never re-derived from stepsOnly.

Reflects the disabled state via aria-disabled only - never native disabled - so the control stays focusable and AT-reachable; the handleClick guard blocks the action while disabled.

<button cngxStepperPrevious>Back</button>