export const formatAgeLabel = (months: number | null | undefined): string => {
    if (months === null || months === undefined) return '—'
    const years = Math.floor(months / 12)
    const remaining = months % 12
    let label = ''
    if (years > 0) label = `${years} an${years > 1 ? 's' : ''}`
    if (remaining > 0) label += `${label ? ' ' : ''}${remaining} mois`
    if (!label) label = '< 1 mois'
    return label
}