harmonic demo: lightly tweak ui coordinates

By slightly extending the end points of the curves out we make use of the screen circle as a clean clipping path.

added 3 commits

• 3e6a36bf...f6f5e618 - 2 commits from branch main
• 179440cb - harmonic demo: lightly tweak ui coordinates

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enabled an automatic merge when the pipeline for 179440cb succeeds

merged