feat: Generalize group_swaps method

- This can now be used for any groupable protocols - not just USV4.

src/encoding/evm/constants.rs

@@ -1,2 +1,16 @@
+use std::{collections::HashSet, sync::LazyLock};
+
 pub const DEFAULT_EXECUTORS_JSON: &str =
     include_str!("../../../src/encoding/config/executor_addresses.json");
+
+/// These protocols support the optimization of grouping swaps.
+///
+/// This requires special encoding to send call data of multiple swaps to a single executor,
+/// as if it were a single swap. The protocol likely uses flash accounting to save gas on token
+/// transfers.
+pub static GROUPABLE_PROTOCOLS: LazyLock<HashSet<&'static str>> = LazyLock::new(|| {
+    let mut set = HashSet::new();
+    set.insert("uniswap_v4");
+    set.insert("balancer_v3");
+    set
+});