import { type SamAnalysis } from './sam-analysis.js';
import { type SamTimelineSummary } from './sam-timeline-summary.js';
/**
 * Adds `has_empty_days_in_range` to each `timeline_summary.months[]` row when the
 * seen window includes a Lisbon calendar day with no analysis covering it.
 */
export declare function withTimelineMonthGapFlags(timeline: null | SamTimelineSummary | undefined, analyses: SamAnalysis[], seenFirst: null | number | undefined, seenLast: null | number | undefined): SamTimelineSummary;