feat(server): initial EVM functionality impl

server/crates/arbiter-server/src/evm/utils.rs

@@ -0,0 +1,9 @@
+use alloy::primitives::U256;
+
+pub fn u256_to_bytes(value: U256) -> [u8; 32] {
+    value.to_le_bytes()
+}
+pub fn bytes_to_u256(bytes: &[u8]) -> Option<U256> {
+    let bytes: [u8; 32] = bytes.try_into().ok()?;
+    Some(U256::from_le_bytes(bytes))
+}