3DViewer app no longer runs after switch to gradle build

The apps/experiments/3DViewer app no longer runs after the repo reorganization and switch to using gradle to build. It looks like there is a missing resource.

This possibly due to a problem noted in one of the comments added to RT-31067:

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Note that the structure of the 3D Viewer app is already "gradle friendly", however, 4 of the resource files are likely in the wrong place and need to be moved as part of this.

At a minimum, the following files need to be moved to apps/experiments/3DViewer/src/main/resources

apps/experiments/3DViewer/src/main/java/com/javafx/experiments/jfx3dviewer/main.fxml
apps/experiments/3DViewer/src/main/java/com/javafx/experiments/jfx3dviewer/navigation.fxml
apps/experiments/3DViewer/src/main/java/com/javafx/experiments/jfx3dviewer/settings.fxml
apps/experiments/3DViewer/src/main/java/com/javafx/experiments/jfx3dviewer/viewer.css
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Additionally, the following should be removed:

apps/experiments/3DViewer/src/main/java/META-INF/MANIFEST.MF