Refactor: Rename map to record

This commit renames `Map` to `Record` and updates all related AST nodes,
binders, type checkers, and runtime values to reflect this change. This
is a semantic change to better align with common programming language
terminology.

src/ast/compiler/binder.rs

@@ -253,12 +253,12 @@ impl Binder {
                 Ok(self.make_node(node.identity.clone(), BoundKind::Tuple { elements: bound_elems }))
             },
 
-            UntypedKind::Map { entries } => {
-                let mut bound_entries = Vec::new();
-                for (k, v) in entries {
-                    bound_entries.push((self.bind(k)?, self.bind(v)?));
+            UntypedKind::Record { fields } => {
+                let mut bound_fields = Vec::new();
+                for (k, v) in fields {
+                    bound_fields.push((self.bind(k)?, self.bind(v)?));
                 }
-                Ok(self.make_node(node.identity.clone(), BoundKind::Map { entries: bound_entries }))
+                Ok(self.make_node(node.identity.clone(), BoundKind::Record { fields: bound_fields }))
             },
 
             UntypedKind::Expansion { call, expanded } => {