Before:
demo_with_tessellate__realistic
                        time:   [328.77 us 329.22 us 329.70 us]
                        change: [-2.6116% -1.1978% +0.2520%] (p = 0.10 > 0.05)
                        No change in performance detected.

demo_no_tessellate      time:   [164.67 us 165.82 us 167.30 us]

demo_only_tessellate    time:   [159.34 us 159.85 us 160.67 us]

After:
demo_with_tessellate__realistic
                        time:   [309.48 us 309.92 us 310.41 us]
                        change: [-7.1042% -5.6164% -4.0262%] (p = 0.00 < 0.05)
                        Performance has improved.

demo_no_tessellate      time:   [160.44 us 161.30 us 162.49 us]
                        change: [-4.5692% -2.8617% -1.3549%] (p = 0.00 < 0.05)
                        Performance has improved.

demo_only_tessellate    time:   [139.45 us 140.23 us 141.25 us]
                        change: [-13.637% -12.245% -10.695%] (p = 0.00 < 0.05)
                        Performance has improved.

Not sure this is the right path. So i didn't bother to port Path::add_point()

Also we might want to fallback to computed vertices for radii >= 20 or add
another precomputed batch.