feat: Remove direct_execution from Solution

This is handled when creating a new TychoEncoder

--- don't change below this line ---
ENG-4246 Took 4 minutes

src/encoding/evm/strategy_encoders.rs

@@ -385,7 +385,6 @@ mod tests {
             // The receiver was generated with `makeAddr("bob") using forge`
             receiver: Bytes::from_str("0x1d96f2f6bef1202e4ce1ff6dad0c2cb002861d3e").unwrap(),
             swaps: vec![swap],
-            direct_execution: true,
             router_address: Bytes::from_str("0x3Ede3eCa2a72B3aeCC820E955B36f38437D01395").unwrap(),
             slippage: None,
             native_action: None,

src/encoding/models.rs

@@ -45,11 +45,6 @@ pub struct Solution {
     pub router_address: Bytes,
     /// If set, the corresponding native action will be executed.
     pub native_action: Option<NativeAction>,
-    /// If set to true, the solution will be encoded to be sent directly to the Executor and
-    /// skip the router. The user is responsible for managing necessary approvals and token
-    /// transfers.
-    #[serde(default)]
-    pub direct_execution: bool,
 }
 
 /// Represents an action to be performed on the native token either before or after the swap.