Variable FeatureRole`Const`

FeatureRole: {
    Bridge: 8;
    Brim: 7;
    Custom: 10;
    ExternalPerimeter: 2;
    Infill: 3;
    Perimeter: 1;
    Skirt: 6;
    SolidInfill: 4;
    Support: 5;
    Travel: 9;
    Unknown: 0;
} = ...

Feature-role indices stored in ToolpathSegments.feature (0 = unknown).