QoL: 3D navigator (#4181)

* Initial integration of ImGuizmo

* Fix mouse capture

* Fix frame update

* Update face color

* Show current camera rotation

* Fix coord mapping

* Update camera rotation from 3d navigator

* Use orthographic

* Render axis

* Make the axis color lighter if at back

* Show axis label

* Fix linux build

* Move to separate method

* Refine

* Add option to show/hide 3d navigator

* Add license info

* Handle dpi scaling

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Co-authored-by: SoftFever <softfeverever@gmail.com>

src/libslic3r/AppConfig.cpp

@@ -189,6 +189,9 @@ void AppConfig::set_defaults()
     if (get("show_gcode_window").empty())
         set_bool("show_gcode_window", true);
 
+    if (get("show_3d_navigator").empty())
+        set_bool("show_3d_navigator", true);
+
 
 #ifdef _WIN32