/** Stream-hash a file's SHA-256 (hex), never buffering the whole file. The
 *  `update` is guarded so a synchronous throw in the data handler rejects the
 *  promise instead of escaping it. */
export declare function fileSha256(filePath: string): Promise<string>;
/** Verify `filePath` against the expected hex SHA-256. On mismatch, rename the
 *  file to `<filePath>.invalidSha` (kept for inspection; won't be picked up, so
 *  the next run re-downloads) and throw. A failed rename is logged (not
 *  swallowed) and reflected in the thrown message. */
export declare function verifyModelFile(filePath: string, expected: string, name: string): Promise<void>;