/**
 * Validates a shard Object ID (hex string, 4-64 chars).
 *
 * The 4-character minimum accommodates abbreviated OIDs used in test
 * fixtures and short internal IDs. Full Git SHA-1 OIDs are 40 chars;
 * SHA-256 OIDs are 64 chars.
 */
export function isValidShardOid(oid) {
    return typeof oid === 'string' && /^[0-9a-fA-F]{4,64}$/.test(oid);
}
