export type DeltaMode = 'full' | 'git-diff' | 'hash-compare';
/**
 * Determines which files have changed since the last index generation.
 * Returns the set of relative file paths that need re-indexing.
 */
export declare function getChangedFiles(cwd: string, sourceDir: string, mode: DeltaMode): string[] | null;
/**
 * Computes a content hash for a file. Used for hash-compare delta mode.
 */
export declare function computeFileHash(filePath: string): string;
