Refactor type checking for globals

Introduces a `global_types` field to `TypeContext` and updates the
`TypeChecker` to pass it down. This allows type checking to correctly
infer and set types for global variables, removing the previous
hardcoded `StaticType::Any` for global addresses.

src/ast/compiler/type_checker.rs

@@ -11,6 +11,8 @@ struct TypeContext<'a> {
     slots: Vec<StaticType>,
     /// Types of captured variables (passed from outer scope)
     upvalue_types: Vec<StaticType>,
+    /// Access to global types for unified resolution
+    global_types: &'a std::cell::RefCell<HashMap<u32, StaticType>>,
     /// The expected parameters of the current function (for 'again' validation)
     current_params_ty: Option<StaticType>,
 }
@@ -19,12 +21,14 @@ impl<'a> TypeContext<'a> {
     fn new(
         slot_count: u32,
         upvalue_types: Vec<StaticType>,
+        global_types: &'a std::cell::RefCell<HashMap<u32, StaticType>>,
         parent: Option<&'a TypeContext<'a>>,
     ) -> Self {
         Self {
             _parent: parent,
             slots: vec![StaticType::Any; slot_count as usize],
             upvalue_types,
+            global_types,
             current_params_ty: None,
         }
     }
@@ -36,7 +40,12 @@ impl<'a> TypeContext<'a> {
                 .get(idx as usize)
                 .cloned()
                 .unwrap_or(StaticType::Any),
-            Address::Global(_) => StaticType::Any, // Globals are dynamic for now
+            Address::Global(idx) => self
+                .global_types
+                .borrow()
+                .get(&idx)
+                .cloned()
+                .unwrap_or(StaticType::Any),
             Address::Upvalue(idx) => self
                 .upvalue_types
                 .get(idx as usize)
@@ -45,11 +54,19 @@ impl<'a> TypeContext<'a> {
         }
     }
 
-    fn set_local_type(&mut self, idx: u32, ty: StaticType) {
+    fn set_type(&mut self, addr: Address, ty: StaticType) {
+        match addr {
+            Address::Local(idx) => {
                 if let Some(slot) = self.slots.get_mut(idx as usize) {
                     *slot = ty;
                 }
             }
+            Address::Global(idx) => {
+                self.global_types.borrow_mut().insert(idx, ty);
+            }
+            _ => {}
+        }
+    }
 }
 
 pub struct TypeChecker {
@@ -76,8 +93,9 @@ impl TypeChecker {
                 }
 
                 // 2. Create the specialized context
-                let root_ctx = TypeContext::new(0, vec![], None);
-                let mut lambda_ctx = TypeContext::new(64, upvalue_types, Some(&root_ctx));
+                let root_ctx = TypeContext::new(0, vec![], &self.global_types, None);
+                let mut lambda_ctx =
+                    TypeContext::new(64, upvalue_types, &self.global_types, Some(&root_ctx));
 
                 // 3. INJECT specialized argument types into slots
                 let arg_tuple_ty = if arg_types.is_empty() {
@@ -147,15 +165,7 @@ impl TypeChecker {
                 captured_by,
                 ..
             } => {
-                match addr {
-                    Address::Local(slot) => ctx.set_local_type(slot, specialized_ty.clone()),
-                    Address::Global(global_index) => {
-                        self.global_types
-                            .borrow_mut()
-                            .insert(global_index, specialized_ty.clone());
-                    }
-                    _ => {}
-                }
+                ctx.set_type(addr, specialized_ty.clone());
                 (
                     BoundKind::Define {
                         name,
@@ -261,20 +271,11 @@ impl TypeChecker {
             } => {
                 let val_typed = self.check_node(*value, ctx)?;
                 let ty = val_typed.ty.clone();
-
-                match addr {
-                    Address::Local(slot) => ctx.set_local_type(slot, ty.clone()),
-                    Address::Global(global_index) => {
-                        self.global_types
-                            .borrow_mut()
-                            .insert(global_index, ty.clone());
-                    }
-                    _ => {}
-                }
+                ctx.set_type(addr, ty.clone());
 
                 (
                     BoundKind::Define {
-                        name,
+                        name: name.clone(),
                         addr,
                         kind: decl_kind,
                         value: Box::new(val_typed),
@@ -285,15 +286,7 @@ impl TypeChecker {
             }
 
             BoundKind::Get { addr, name } => {
-                let ty = if let Address::Global(idx) = addr {
-                    self.global_types
-                        .borrow()
-                        .get(&idx)
-                        .cloned()
-                        .unwrap_or(StaticType::Any)
-                } else {
-                    ctx.get_type(addr)
-                };
+                let ty = ctx.get_type(addr);
                 (
                     BoundKind::Get {
                         addr,
@@ -306,12 +299,7 @@ impl TypeChecker {
             BoundKind::Set { addr, value } => {
                 let val_typed = self.check_node(*value, ctx)?;
                 let ty = val_typed.ty.clone();
-
-                if let Address::Local(idx) = addr {
-                    ctx.set_local_type(idx, ty.clone());
-                } else if let Address::Global(idx) = addr {
-                    self.global_types.borrow_mut().insert(idx, ty.clone());
-                }
+                ctx.set_type(addr, ty.clone());
 
                 (
                     BoundKind::Set {
@@ -394,7 +382,8 @@ impl TypeChecker {
                 }
 
                 // 2. Create nested context for lambda body
-                let mut lambda_ctx = TypeContext::new(64, upvalue_types, Some(ctx));
+                let mut lambda_ctx =
+                    TypeContext::new(64, upvalue_types, ctx.global_types, Some(ctx));
 
                 // 3. Check parameters and body
                 let params_typed =