QoL: Add auto perspective (#8312)

* ImGuizmo: Comment out unused code

* 3DNav: Avoid gimbal lock by using polar coordinates

* 3DNav: Make sure top and bottom are oriented correctly

* Add auto perspective

* Add options

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

src/libslic3r/AppConfig.cpp

@@ -170,6 +170,9 @@ void AppConfig::set_defaults()
     if (get("use_perspective_camera").empty())
         set_bool("use_perspective_camera", true);
 
+    if (get("auto_perspective").empty())
+        set_bool("auto_perspective", false);
+
     if (get("use_free_camera").empty())
         set_bool("use_free_camera", false);