Refactor: Implement Record Layouts and Optimized Field Access

Introduces a new `RecordLayout` system for efficient and type-safe
record handling.

Key changes:
- `RecordLayout` struct with `O(1)` field lookup using FMap
  optimization.
- Field accessors (`.name`) are now first-class callable values.
- Parser recognizes dot-prefixed identifiers as field accessors.
- Binder and TypeChecker handle field accessors.
- Optimizer transforms field accessor calls into specialized `GetField`
  nodes.
- VM executes `GetField` efficiently by directly accessing record
  values.
- Adds a new `records.myc` example showcasing record features.
- Improves comparison logic for records to use pointer equality for
  layout.

src/ast/compiler/analyzer.rs

@@ -83,6 +83,20 @@ impl<'a> Analyzer<'a> {
                 )
             }
 
+            BoundKind::FieldAccessor(k) => (BoundKind::FieldAccessor(*k), Purity::Pure),
+
+            BoundKind::GetField { rec, field } => {
+                let rec_m = self.visit(Rc::new((**rec).clone()));
+                let p = rec_m.ty.purity;
+                (
+                    BoundKind::GetField {
+                        rec: Box::new(rec_m),
+                        field: *field,
+                    },
+                    p,
+                )
+            }
+
             BoundKind::Set { addr, value } => {
                 let val_m = self.visit(Rc::new((**value).clone()));
                 (
@@ -313,6 +327,9 @@ impl NodeExt for BoundKind<crate::ast::types::StaticType> {
             BoundKind::Define { value, .. } | BoundKind::Set { value, .. } => {
                 f(value);
             }
+            BoundKind::GetField { rec, .. } => {
+                f(rec);
+            }
             BoundKind::Lambda { params, body, .. } => {
                 f(params);
                 f(body);