feat: Add tail call optimization

Introduce a TCO pass to the compiler and modify the VM to handle tail
calls.
This allows for deep recursion without stack overflow.

src/ast/compiler/bound_nodes.rs

@@ -9,7 +9,7 @@ pub enum Address {
     Global(u32),  // Index in the global environment vector
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub enum BoundKind {
     Nop,
     Constant(Value),
@@ -47,6 +47,11 @@ pub enum BoundKind {
         args: Vec<Node<BoundKind, StaticType>>,
     },
 
+    TailCall {
+        callee: Box<Node<BoundKind, StaticType>>,
+        args: Vec<Node<BoundKind, StaticType>>,
+    },
+
     Block {
         exprs: Vec<Node<BoundKind, StaticType>>,
     },