feat: Add comments to AST nodes

This commit introduces support for comments within the AST nodes.
Comments are now parsed by the lexer and stored within the `Token`
struct.
These comments are then propagated through various compiler phases,
including
the `Node` struct, ensuring they are preserved in the Abstract Syntax
Tree.
This change enhances the AST's ability to retain source code
information,
which can be valuable for debugging and analysis.

src/ast/compiler/optimizer/engine.rs

@@ -724,6 +724,7 @@ impl Optimizer {
         Rc::new(Node {
             identity: node.identity.clone(),
             kind: new_kind,
+            comments: node.comments.clone(),
             ty: metrics,
         })
     }
@@ -780,6 +781,7 @@ impl Optimizer {
             _ => return node_rc.clone(),
         };
         Rc::new(Node {
+            comments: node.comments.clone(),
             identity: node.identity.clone(),
             kind: new_kind,
             ty: node.ty.clone(),

src/ast/compiler/optimizer/folder.rs

@@ -19,11 +19,13 @@ impl<'a> Folder<'a> {
         let typed_original = Rc::new(Node {
             identity: template.identity.clone(),
             kind: NodeKind::Constant(val.clone()),
+            comments: template.comments.clone(),
             ty: ty.clone(),
         });
         Node {
             identity: template.identity.clone(),
             kind: NodeKind::Constant(val),
+            comments: template.comments.clone(),
             ty: NodeMetrics {
                 original: typed_original,
                 purity: Purity::Pure,
@@ -36,11 +38,13 @@ impl<'a> Folder<'a> {
         let typed_original = Rc::new(Node {
             identity: template.identity.clone(),
             kind: NodeKind::Nop,
+            comments: template.comments.clone(),
             ty: StaticType::Void,
         });
         Node {
             identity: template.identity.clone(),
             kind: NodeKind::Nop,
+            comments: template.comments.clone(),
             ty: NodeMetrics {
                 original: typed_original,
                 purity: Purity::Pure,

src/ast/compiler/optimizer/substitution_map.rs

@@ -231,6 +231,7 @@ impl SubstitutionMap {
         Rc::new(Node {
             identity: node.identity.clone(),
             kind: new_kind,
+            comments: node.comments.clone(),
             ty: metrics,
         })
     }