[CircularProgressIndicator] Fix full circle track seam artifact

[Nanamare]

Summary

• When CircularDrawingDelegate.drawArc() renders a full circle (360°) track with trackCornerRadius > 0, the start/end caps or rounded blocks overlap at 0°, producing a visible seam artifact
• Replace drawArc() with drawOval() for full circle tracks — drawOval has no start/end point, so the seam is eliminated entirely
• Partial arcs (active indicators) continue to use the existing drawArc() logic unchanged

Fix-CircularProgressIndicator.mov

Demo branch

A separate branch with catalog app changes to reproduce and verify the fix:
demo/circular-indicator-seam-reproduction

It includes:

• Catalog theme switched to Theme.Material3.DayNight.NoActionBar
• Custom CircularProgressIndicator style with trackCornerRadius=8dp to make the artifact visible
• Full diff against this PR

Test plan

• Verify CircularProgressIndicator with trackCornerRadius > 0 renders a seamless full circle track
• Verify determinate indicator (partial arc) still draws correctly with rounded corners
• Verify indeterminate animation renders correctly
• Verify wavy effect paths are unaffected (bypass the drawOval path)
• Run ./gradlew test — JVM tests pass

Fixes #5027

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