A Concept status now renders as a CIBG "melding" (warning) with its own
verwijderen/openen actions, matching the real CIBG pattern for an in-progress
application, instead of sharing the keuzelijst card shape used by resolved
statuses. Alert atom switches from a hand-rolled surface to the vendored
`.feedback` classes with a visually-hidden icon label per CIBG's a11y
requirement.