/**
 * Phase 4a — printable diff between two lockfile snapshots.
 *
 * Used by `cursell update` to show the user what's about to change,
 * by `cursell verify` to surface same-version-different-hash drift,
 * and by tests/audit. Output is plain text (no ANSI codes).
 */
import type { Lockfile, AgentEntry } from "./schema.js";
export interface DiffEntry {
    slug: string;
    kind: "added" | "removed" | "version_changed" | "hash_drift" | "registry_changed";
    before?: AgentEntry;
    after?: AgentEntry;
    /** Human-readable summary line. */
    message: string;
}
export interface LockfileDiff {
    entries: DiffEntry[];
    /** Aggregate flag: `cursell verify` should fail on hash_drift. */
    hashDrift: boolean;
    /** Registry change is reported but never fails verify (per plan). */
    registryChanged: boolean;
}
export declare function diffLockfiles(before: Lockfile | null, after: Lockfile | null): LockfileDiff;
/** Render a diff as a multi-line plain-text report. */
export declare function formatDiff(d: LockfileDiff): string;