feat: add memory db key manager util function (#6444)

This helps with creating a few keys from seed words

base_layer/core/src/transactions/key_manager/memory_db_key_manager.rs

@@ -65,6 +65,27 @@ pub fn create_memory_db_key_manager_with_range_proof_size(
     )
 }
 
+pub fn create_memory_db_key_manager_from_seed(
+    seed: CipherSeed,
+    rangeproof_size: usize,
+) -> Result<MemoryDbKeyManager, KeyManagerServiceError> {
+    let connection = DbConnection::connect_url(&DbConnectionUrl::MemoryShared(random_string(8)))?;
+    let cipher = seed;
+
+    let mut key = [0u8; size_of::<Key>()];
+    OsRng.fill_bytes(&mut key);
+    let key_ga = Key::from_slice(&key);
+    let db_cipher = XChaCha20Poly1305::new(key_ga);
+    let factory = CryptoFactories::new(rangeproof_size);
+
+    TransactionKeyManagerWrapper::<KeyManagerSqliteDatabase<DbConnection>>::new(
+        cipher,
+        KeyManagerDatabase::new(KeyManagerSqliteDatabase::init(connection, db_cipher)),
+        factory,
+        WalletType::default(),
+    )
+}
+
 pub fn create_memory_db_key_manager() -> Result<MemoryDbKeyManager, KeyManagerServiceError> {
     create_memory_db_key_manager_with_range_proof_size(64)
 }

base_layer/core/src/transactions/key_manager/mod.rs

@@ -42,6 +42,7 @@ mod memory_db_key_manager;
 pub use inner::TransactionKeyManagerInner;
 pub use memory_db_key_manager::{
     create_memory_db_key_manager,
+    create_memory_db_key_manager_from_seed,
     create_memory_db_key_manager_with_range_proof_size,
     MemoryDbKeyManager,
 };