sdk: Rename smt_native to monotree

src/sdk/src/lib.rs

@@ -28,7 +28,7 @@ pub mod blockchain;
 pub mod dark_tree;
 
 /// Native (non-wasm, non-ff) Sparse Merkle Tree
-pub mod smt_native;
+pub mod monotree;
 
 /// Contract deployment utilities
 pub mod deploy;

src/sdk/src/smt_native/mod.rs → src/sdk/src/monotree/mod.rs

@@ -33,6 +33,9 @@ pub type Proof = Vec<(bool, Vec<u8>)>;
 /// The key to be used to restore the latest `root`
 pub const ROOT_KEY: &Hash = b"_______monotree::headroot_______";
 
+use std::sync::LazyLock;
+pub static EMPTY_HASH: LazyLock<Hash> = LazyLock::new(|| *blake3::hash(&[]).as_bytes());
+
 pub mod bits;
 
 pub mod node;