MRTK3 Example Scene Polish

[AMollis]

Overview

This change polishes the existing MRTK3 example scenes. Things fixed

• Where possible, the scene's description panel was updated to include an "Object Manipulator" so the scene content can be moved
• The 'Simple Profiler' added to every scene
• Hand Rays disabled by default in eye-gaze interaction scene
• Updated 'Example Hand Menu' to initialize its state based on interactors' enablement at start time.
• The dictation example now re-enables keyword recognition once dictation stops.
• Improved 'Solver Example' scene layout
• Improved 'Speech Input Example' scene layout, and change 'global speech' sample to change shape/mesh of the game objects to better demonstrate using stateful interactor's keyword feature.
• Improved 'Dwell Example' scene layout
• Improved all eye gaze scene layouts
• Improved 'Disable Interactor Example' scene layout
• Improved 'Virtualized Scroll Rect List' scene layout, and added touch scrolling to the list
• Improved 'Scrolling Example' scene layout, and improved its performance by reducing game objects
• Updated 'Disable Interactor Example' so it's harder to get stuck.
• Fixed 'Eye Tracking Visualizer Example' scene so eye tracking recording works on device
• Fixing text example scene to use TextMeshPro

Changes

• Fixes: MRTK3's Record Eye Gaze Sample is not working #11731
• Fixes: Disable hand rays by default in MRTK3 eye gaze examples #11730
• Fixes: You can get stuck in MRTK3 DisableInteractors Example if you turn off all interactors or select "VR" mode #11726
• Fixes: MRTK3 DictionExample doesn't re-enable keyword recognition after dictation is enabled and disabled again #11725

Verification

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