Investigate the chroma compression limits around yellow and green

[KevinJW]

During the meeting on the 08th Feb 2023 we discussed issues relating to the gamut compression pulling values inside of even the Rec 709 gamut in the green and yellow area.

This may require us to generate values of M beyond the nominal 100 limit.

We discussed if there would be a better option that better aligned the compressed boundary lobe to the position of the cusp.

[priikone]

This should be re-tested with v29, which reduced chroma compression because of the change to Dim surround. CC: @alexfry