fix: Post merge's fixes

Because of the renaming, git couldn't identify the new files and handle the conflicts gracefully.
Copied implementation for ExecutorStrategyEncoder from main

Rollbacked on decision to encode the executor address and selector inside the SwapEncoders. This is only necessary for certain strategies. So it should be done at the strategy level

--- don't change below this line ---
ENG-4081 Took 35 minutes

src/encoding/swap_encoder.rs

@@ -14,4 +14,5 @@ pub trait SwapEncoder: Sync + Send {
         encoding_context: EncodingContext,
     ) -> Result<Vec<u8>, EncodingError>;
     fn executor_address(&self) -> &str;
+    fn executor_selector(&self) -> &str;
 }