export interface DiffLine {
    kind: ' ' | '+' | '-';
    text: string;
}
export interface DiffHunk {
    oldStart: number;
    oldLines: number;
    newStart: number;
    newLines: number;
    lines: DiffLine[];
    filePath?: string;
}
export interface DiffPayload {
    hunks: DiffHunk[];
    addedLines: number;
    removedLines: number;
}
export declare function computeLineDiff(before: string, after: string): DiffPayload | null;