feat(gui): Migrate _render_shader_live_editor to imgui_window scope

src/imgui_scopes.py

@@ -20,13 +20,13 @@ class ImGuiScope:
   self._entered = False
 
  def __enter__(self) -> bool | tuple:
-  result = self._begin_fn(*self._args, **self._kwargs)
-  if isinstance(result, tuple):
-   self._opened = result[0]
+  self._opened = self._begin_fn(*self._args, **self._kwargs)
+  if isinstance(self._opened, tuple):
+   self._entered = bool(self._opened[0])
+   return self._opened
   else:
-   self._opened = result
-  self._entered = bool(self._opened)
-  return self._opened
+   self._entered = bool(self._opened)
+   return self._opened
 
  def __exit__(self, *args: object) -> bool:
   if self._entered: