/**
 * Storage backend abstraction for file persistence.
 * Implementations: DiskFileStorage (local dev), R2FileStorage (prod).
 */
export interface FileStorage {
  write(key: string, data: Buffer): Promise<void>;
  read(key: string): Promise<Buffer>;
  delete(key: string): Promise<void>;
  exists(key: string): Promise<boolean>;
}

export const FILE_STORAGE = Symbol("FILE_STORAGE");