Add 'Goto entity' support for the new Editor camera (#743)

* add find entity in viewport functionality to new camera

* fix AZ_CVAR usage

* updates following review feedback

- updated comment styles from /// to //!
- retrieve fov of camera (add test for fov access)

* update namespace naming, fix AZ_CVAR usage

* update missed namespace and use AZ::Transform::CreateLookAt

* add missing include

* move EditorViewportSettings to EditorLib

* update DLL import/export API and rename namespace usage

Code/Sandbox/Editor/EditorViewportSettings.cpp

@@ -16,7 +16,7 @@
 #include <AzCore/Settings/SettingsRegistry.h>
 #include <AzCore/std/string/string_view.h>
 
-namespace Editor
+namespace SandboxEditor
 {
     constexpr AZStd::string_view GridSnappingSetting = "/Amazon/Preferences/Editor/GridSnapping";
     constexpr AZStd::string_view GridSizeSetting = "/Amazon/Preferences/Editor/GridSize";
@@ -113,4 +113,4 @@ namespace Editor
             registry->Set(ShowGridSetting, showing);
         }
     }
-} // namespace Editor
+} // namespace SandboxEditor