feat: Add evm feature gate

- Move all evm code inside evm directory
- StrategyEncoder:
  - Kept StrategyEncoder trait but created a new one: EVMStrategyEncoder to implement encode_protocol_header (that is evm specific).
  - All StrategyEncoders implement both traits now
  - Renamed DefaultStrategySelector -> EVMStrategySelector
- RouterEncoder:
  - Created a RouterEncoder trait and a EVMRouterEncoder that implements it
- Moved utils inside evm directory as well
- Renamed config.json -> executor_addresses.json and moved it to a higher config directory
- Make alloy optional and dependent on the evm feature gate

--- don't change below this line ---
ENG-4075 <#DTT#>

src/encoding/evm/swap_encoder/builder.rs

@@ -0,0 +1,26 @@
+use crate::encoding::{
+    evm::swap_encoder::encoders::{BalancerV2SwapEncoder, UniswapV2SwapEncoder},
+    swap_encoder::SwapEncoder,
+};
+
+pub struct SwapEncoderBuilder {
+    protocol_system: String,
+    executor_address: String,
+}
+
+impl SwapEncoderBuilder {
+    pub fn new(protocol_system: &str, executor_address: &str) -> Self {
+        SwapEncoderBuilder {
+            protocol_system: protocol_system.to_string(),
+            executor_address: executor_address.to_string(),
+        }
+    }
+
+    pub fn build(self) -> Result<Box<dyn SwapEncoder>, String> {
+        match self.protocol_system.as_str() {
+            "uniswap_v2" => Ok(Box::new(UniswapV2SwapEncoder::new(self.executor_address))),
+            "vm:balancer_v2" => Ok(Box::new(BalancerV2SwapEncoder::new(self.executor_address))),
+            _ => Err(format!("Unknown protocol system: {}", self.protocol_system)),
+        }
+    }
+}