feat(codegen): support multi-validators

* rename force_wrap to force
* add a bunch of builder methods to Term<Name>
* refactor one tiny location to show off builder methods
* split generate into `generate` and `generate_test`
* create wrap_as_multi_validator function

Co-authored-by: Kasey White <kwhitemsg@gmail.com>

examples/acceptance_tests/script_context/validators/basic.ak

@@ -4,8 +4,8 @@ use aiken/transaction.{NoDatum, ScriptContext, Spend, TransactionId}
 use aiken/transaction/credential.{VerificationKeyCredential}
 use aiken/transaction/value
 
-validator spend {
-  fn(_datum: Void, _redeemer: Void, ctx: ScriptContext) {
+validator {
+  fn spend(_datum: Void, _redeemer: Void, ctx: ScriptContext) {
     [
       assert_id(ctx.transaction),
       assert_purpose(ctx.purpose),

examples/acceptance_tests/script_context/validators/deploy.ak

@@ -5,8 +5,8 @@ use aiken/list
 use aiken/transaction.{DatumHash, InlineDatum, ScriptContext}
 use aiken/transaction/credential.{Inline, VerificationKeyCredential}
 
-validator spend {
-  fn(datum: Data, _redeemer: Data, ctx: ScriptContext) {
+validator {
+  fn spend(datum: Data, _redeemer: Data, ctx: ScriptContext) {
     [
       assert_datum(datum),
       assert_datums(ctx.transaction.datums),

examples/acceptance_tests/script_context/validators/mint.ak

@@ -3,8 +3,8 @@ use aiken/list
 use aiken/transaction.{Mint, ScriptContext}
 use aiken/transaction/value
 
-validator mint {
-  fn(redeemer: Data, ctx: ScriptContext) {
+validator {
+  fn mint(redeemer: Data, ctx: ScriptContext) {
     [
       assert_purpose(ctx),
       assert_mint(ctx.purpose, ctx.transaction),

examples/acceptance_tests/script_context/validators/withdrawals.ak

@@ -5,8 +5,8 @@ use aiken/transaction/credential.{
   Inline, ScriptCredential, VerificationKeyCredential,
 }
 
-validator spend {
-  fn(_datum: Void, _redeemer: Void, ctx: ScriptContext) {
+validator {
+  fn spend(_datum: Void, _redeemer: Void, ctx: ScriptContext) {
     let alice =
       Inline(
         VerificationKeyCredential(