HackStudio: Make wrapping modes consistent

We were only setting the wrapping mode when triggering the action. So:
- Any editors open without triggering a wrapping-mode action would have
  the default (WrapAtWords) instead of the selected item (NoWrap).
- Any editors opened after triggering an action would have the default
  too.

This fixes both situations, by:
- Storing the current wrapping mode in `m_wrapping_mode`. Later this
  could be loaded from the config.
- Changing that value any time a wrapping-mode action is triggered.
- Setting the wrapping mode on newly-created editors.

Userland/DevTools/HackStudio/HackStudioWidget.h

@@ -253,6 +253,7 @@ private:
     RefPtr<Gfx::Font> m_editor_font;
     RefPtr<GUI::Action> m_editor_font_action;
 
+    GUI::TextEditor::WrappingMode m_wrapping_mode { GUI::TextEditor::NoWrap };
     GUI::ActionGroup m_wrapping_mode_actions;
     RefPtr<GUI::Action> m_no_wrapping_action;
     RefPtr<GUI::Action> m_wrap_anywhere_action;