export interface SyncSource {
    source: string;
    commit: string;
    version: string | null;
}
export interface SyncSnapshot {
    version: 1;
    updatedAt: string;
    sources: SyncSource[];
}
/**
 * Extract the first semver from a changelog: matches the first `## x.y.z`
 * heading (e.g. `## 1.2.3`). Returns null when no match is found.
 */
export declare function parseChangelogVersion(changelogText: string): string | null;
/** Read `<skillsDir>/.sync.json`. Returns null when missing or unparseable. */
export declare function readSyncSnapshot(skillsDir: string): Promise<SyncSnapshot | null>;
/** Atomically write `<skillsDir>/.sync.json` (temp file + rename). */
export declare function writeSyncSnapshot(skillsDir: string, snapshot: SyncSnapshot): Promise<void>;
/** Update the entry matching `entry.source` or append it when missing. */
export declare function upsertSyncSource(snapshot: SyncSnapshot, entry: SyncSource): SyncSnapshot;
/**
 * Diff two file inventories (relative path -> content hash). Files whose
 * path and hash are identical in both maps are skipped. Results are
 * aggregated by skill name:
 *  - paths matching `skills/<bucket>/<name>/...` map to `<name>`
 *  - any other path maps to its first path segment
 */
export declare function computeSkillDelta(oldEntries: Map<string, string>, newEntries: Map<string, string>): {
    added: string[];
    removed: string[];
    modified: string[];
};
/**
 * Rewrite the pinnedCommit of a matching source inside raw manifest JSON text.
 * Format-preserving (regex replace, not parse/re-serialize). Throws when the
 * source has no pinnedCommit entry.
 */
export declare function rewritePinnedCommit(raw: string, source: string, newHead: string): string;