runtime, macros: unify NaN-boxed value API under ValueVariant trait

fix-vm/src/instructions/closures.rs

@@ -17,7 +17,7 @@ pub(crate) fn op_make_thunk<'gc, M: Machine<'gc>>(
             env: m.env(),
         }),
     );
-    m.push(Value::new_gc(thunk));
+    m.push(Value::new(thunk));
     Step::Continue(())
 }
 
@@ -38,7 +38,7 @@ pub(crate) fn op_make_closure<'gc, M: Machine<'gc>>(
             pattern: None,
         },
     );
-    m.push(Value::new_gc(closure));
+    m.push(Value::new(closure));
     Step::Continue(())
 }
 
@@ -88,6 +88,6 @@ pub(crate) fn op_make_pattern_closure<'gc, M: Machine<'gc>>(
             pattern: Some(pattern),
         },
     );
-    m.push(Value::new_gc(closure));
+    m.push(Value::new(closure));
     Step::Continue(())
 }