Completeness badge does not update when a conditional gate changes after validation errors are shown

I think there are two related but separable concerns here.

First, Field Group Complete (FGC) needs to recompute when a gate field changes, not only when the currently errored field itself changes (or blurs). In this case, the boolean checkbox is what changes whether the dependent field should count toward completeness, so field-specific handling on the errored dependent field is not enough.

Second, I do not think FGC necessarily needs to fully interpret the Form States API #states expression in order to decide completeness. It may be reasonable to inspect data-drupal-states to discover that one field depends on another and therefore know when to trigger a recompute. But the actual completeness calculation may need to stay generic: look at the current rendered state of the form and decide whether the relevant required, required-on-publish, or errored controls are currently visible/applicable inside the field group.

That avoids making FGC responsible for reimplementing all of Drupal states logic or custom states semantics. For example, require_on_publish is not a core state with a universal meaning; it is meaningful because another module adds behavior around it. Similarly, Conditional Fields may use states-style expressions, but the important result for FGC is whether the field is currently visible/applicable and should count.

So my current leaning is:

• Maybe use state/dependency information if helpful to know when a gate change should trigger a recompute.
• Use the actual DOM/form state to decide whether a field counts toward completeness.

That seems like a reasonable middle ground: FGC can react to conditional dependencies without becoming a second implementation of Drupal states or of module-specific states such as required-on-publish.