feat: Implement SplitSwapStrategyEncoder

The strategy works as follows:
- Manage approvals needed
- Compute min amount (if check amount is any):
  - if slippage is defined, apply slippage on the expected amount and take the min value between that and the check amount
  - if not, it's just the check amount
- Iterate through the swaps
  - call the corresponding swap encoder to encode the swap
  - add swap header (tokens indexes and split)
  - ple encode the swaps
- Add extra inputs (amounts, token addresses, min amount, (un)wrap, number of tokens and receiver)

Misc:
- Move executor address and selector encoding inside the SwapEncoder
- Add default executor_selector to SwapEncoder
- Pass router address inside the SplitSwapStrategyEncoder
- Move Permit2 inside the SplitSwapStrategyEncoder. It is a responsibility and a specificity of the strategy to need permit2 approvals

--- don't change below this line ---
ENG-4081 Took 1 hour 21 minutes

src/encoding/evm/approvals/permit2.rs

@@ -1,13 +1,14 @@
 use std::{str::FromStr, sync::Arc};
 
 use alloy::{
-    primitives::{aliases::U48, Address, Bytes as AlloyBytes, TxKind, U160},
+    primitives::{aliases::U48, Address, Bytes as AlloyBytes, ChainId, TxKind, U160, U256},
     providers::{Provider, RootProvider},
     rpc::types::{TransactionInput, TransactionRequest},
     signers::{local::PrivateKeySigner, SignerSync},
     transports::BoxTransport,
 };
-use alloy_primitives::{ChainId, Signature, U256};
+#[allow(deprecated)]
+use alloy_primitives::Signature;
 use alloy_sol_types::{eip712_domain, sol, SolStruct, SolValue};
 use chrono::Utc;
 use num_bigint::BigUint;
@@ -108,6 +109,7 @@ impl Permit2 {
         }
     }
     /// Creates permit single and signature
+    #[allow(deprecated)]
     pub fn get_permit(
         &self,
         spender: &Bytes,