fix: 🐛 add func getDatasetProofRootHash

(update datasetProof contract) add function getDatasetProofRootHash

✅ Closes: #354

src/v0.8/interfaces/module/IDatasetsProof.sol

@@ -99,6 +99,15 @@ interface IDatasetsProof {
         uint64 _datasetId
     ) external view returns (uint64);
 
+    /// @notice Retrieves the Merkle root hash of the dataset for the specified dataset ID and data type.
+    /// @param _datasetId The ID of the dataset for which to retrieve the Merkle root hash.
+    /// @param _dataType The type of data for which to retrieve the Merkle root hash.
+    /// @return rootHash The Merkle root hash of the dataset.
+    function getDatasetProofRootHash(
+        uint64 _datasetId,
+        DatasetType.DataType _dataType
+    ) external view returns (bytes32 rootHash);
+
     ///@notice Check if a dataset has a car id
     function isDatasetContainsCar(
         uint64 _datasetId,

src/v0.8/module/dataset/DatasetsProof.sol

@@ -577,6 +577,20 @@ contract DatasetsProof is
         return datasetProof.completedHeight;
     }
 
+    /// @notice Retrieves the Merkle root hash of the dataset for the specified dataset ID and data type.
+    /// @param _datasetId The ID of the dataset for which to retrieve the Merkle root hash.
+    /// @param _dataType The type of data for which to retrieve the Merkle root hash.
+    /// @return rootHash The Merkle root hash of the dataset.
+    function getDatasetProofRootHash(
+        uint64 _datasetId,
+        DatasetType.DataType _dataType
+    ) external view onlyNotZero(_datasetId) returns (bytes32 rootHash) {
+        DatasetType.DatasetProof storage datasetProof = datasetProofs[
+            _datasetId
+        ];
+        rootHash = datasetProof.getDatasetRootHash(_dataType);
+    }
+
     ///@notice Check if a dataset proof all completed
     function isDatasetProofallCompleted(
         uint64 _datasetId,

src/v0.8/module/dataset/library/proof/DatasetProofLIB.sol

@@ -163,6 +163,23 @@ library DatasetProofLIB {
         return self.proofSubmitter;
     }
 
+    /// @notice Retrieves the root hash of the dataset proof for the specified data type.
+    /// @param self The storage reference to the dataset proof.
+    /// @param _dataType The type of data for which to retrieve the root hash.
+    /// @return The root hash of the dataset proof.
+    function getDatasetRootHash(
+        DatasetType.DatasetProof storage self,
+        DatasetType.DataType _dataType
+    ) internal view returns (bytes32) {
+        DatasetType.Proof storage proof;
+        if (_dataType == DatasetType.DataType.Source) {
+            proof = self.sourceProof;
+        } else {
+            proof = self.mappingFilesProof;
+        }
+        return proof.rootHash;
+    }
+
     /// @notice Check if a dataset has submitter
     /// @param self The dataset from which to retrieve the source dataset proof.
     /// @param submitter The address being compared.