fn execute_route(
env: soroban_sdk::Env,
user: soroban_sdk::Address,
recipient: soroban_sdk::Address,
token_in: soroban_sdk::Address,
amount_in: i128,
final_token_out: soroban_sdk::Address,
final_amount_out_min: i128,
legs: soroban_sdk::Vec,
) -> i128