feat: support CompactThetaSketch

Author: ZENOTME

datasketches/src/hash/mod.rs

@@ -35,7 +35,8 @@ pub(crate) use self::xxhash::XxHash64;
 /// and seed are identical for both sketches, otherwise the assumed 1:1 relationship between the
 /// original source key value and the hashed bit string would be violated. Once you have developed
 /// a history of stored sketches you are stuck with it.
-pub(crate) const DEFAULT_UPDATE_SEED: u64 = 9001;
+/// The default seed used for hashing.
+pub const DEFAULT_UPDATE_SEED: u64 = 9001;
 
 /// Computes and checks the 16-bit seed hash from the given long seed.
 ///