Rework parameter validation to work from 'Constant' instead of 'Term'

This simplifies the code and makes it more efficient as we no longer need to wrap and unwrap constant terms constantly.

crates/aiken-project/src/blueprint/error.rs

@@ -6,7 +6,7 @@ use aiken_lang::ast::Span;
 use miette::{Diagnostic, NamedSource};
 use owo_colors::{OwoColorize, Stream::Stdout};
 use std::fmt::Debug;
-use uplc::ast::{DeBruijn, Term};
+use uplc::ast::Constant;
 
 #[derive(Debug, thiserror::Error, Diagnostic)]
 pub enum Error {
@@ -48,12 +48,12 @@ pub enum Error {
     ))]
     ParameterizedValidator { n: usize },
 
-    #[error("I failed to infer what should be the schema of a given parameter to apply.")]
+    #[error("I stumble upon something else than a constant when I expected one.")]
     #[diagnostic(code("aiken:blueprint::apply::malformed::argument"))]
     #[diagnostic(help(
-        "I couldn't figure out the schema corresponding to a term you've given. Here's a possible hint about why I failed: {hint}"
+        "Parameters applied to blueprints must be constant; they cannot be lambdas or delayed terms."
     ))]
-    UnableToInferArgumentSchema { hint: String },
+    NonConstantParameter,
 
     #[error("I couldn't find a definition corresponding to a reference.")]
     #[diagnostic(code("aiken::blueprint::apply::unknown::reference"))]
@@ -70,10 +70,7 @@ pub enum Error {
         serde_json::to_string_pretty(&schema).unwrap().if_supports_color(Stdout, |s| s.green()),
         term.to_pretty().if_supports_color(Stdout, |s| s.red()),
     ))]
-    SchemaMismatch {
-        schema: Schema,
-        term: Term<DeBruijn>,
-    },
+    SchemaMismatch { schema: Schema, term: Constant },
 
     #[error(
         "I discovered a discrepancy of elements between a given tuple and its declared schema."