Align output of tx simulate with other Aiken's commands.

And also return a structured output as JSON, so it's more easily used
  by other tools.

  ```
       Parsing script context
    Simulating 78ec148ea647cf9969446891af31939c5d57b275a2455706782c6183ef0b62f1
      Redeemer Spend → 0

  {"mem":151993,"cpu":58180696}
  ```

crates/uplc/src/machine/cost_model.rs

@@ -18,7 +18,7 @@ macro_rules! hashmap {
 }
 
 /// Can be negative
-#[derive(Debug, Clone, PartialEq, Eq, Copy)]
+#[derive(Debug, Clone, PartialEq, Eq, Copy, serde::Serialize)]
 pub struct ExBudget {
     pub mem: i64,
     pub cpu: i64,

crates/uplc/src/tx.rs

@@ -35,6 +35,7 @@ pub fn eval_phase_two(
     initial_budget: Option<&ExBudget>,
     slot_config: &SlotConfig,
     run_phase_one: bool,
+    with_redeemer: fn(&Redeemer) -> (),
 ) -> Result<Vec<Redeemer>, Error> {
     let redeemers = tx.transaction_witness_set.redeemer.as_ref();
 
@@ -52,6 +53,8 @@ pub fn eval_phase_two(
             let mut remaining_budget = *initial_budget.unwrap_or(&ExBudget::default());
 
             for redeemer in rs.iter() {
+                with_redeemer(redeemer);
+
                 let redeemer = eval::eval_redeemer(
                     tx,
                     utxos,
@@ -87,6 +90,7 @@ pub fn eval_phase_two_raw(
     initial_budget: (u64, u64),
     slot_config: (u64, u64, u32),
     run_phase_one: bool,
+    with_redeemer: fn(&Redeemer) -> (),
 ) -> Result<Vec<Vec<u8>>, Error> {
     let multi_era_tx = MultiEraTx::decode(Era::Babbage, tx_bytes)
         .or_else(|_| MultiEraTx::decode(Era::Alonzo, tx_bytes))?;
@@ -122,6 +126,7 @@ pub fn eval_phase_two_raw(
                 Some(&budget),
                 &sc,
                 run_phase_one,
+                with_redeemer,
             ) {
                 Ok(redeemers) => Ok(redeemers
                     .iter()

crates/uplc/src/tx/tests.rs

@@ -246,6 +246,7 @@ fn test_eval() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -516,6 +517,7 @@ fn test_eval_1() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -621,6 +623,7 @@ fn test_eval_2() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -885,6 +888,7 @@ fn test_eval_3() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -987,6 +991,7 @@ fn test_eval_4() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .is_err());
         }
@@ -1069,6 +1074,7 @@ fn test_eval_5() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -1173,6 +1179,7 @@ fn test_eval_6() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -1277,6 +1284,7 @@ fn test_eval_7() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -1532,6 +1540,7 @@ fn test_eval_8() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
 
@@ -1632,6 +1641,7 @@ fn eval_missing_redeemer() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .unwrap();
         }
@@ -1711,6 +1721,7 @@ fn eval_extraneous_redeemer() {
                 Some(&initial_budget),
                 &slot_config,
                 false,
+                |_| (),
             )
             .is_err());
         }