[fummicc1]

Closes #47. Targets modernize-ios17-swift6 so it ships as part of v2.0.0.

The problem

#47 reports that the roulette does not look like a roulette:

1. Labels sit around the middle instead of near the outer edge
2. Labels are not rotated to follow their wedge
3. Every separator converges to a point in the centre, which is visually noisy while spinning

The approach

A new RouletteStyle, applied with a .rouletteStyle(_:) view modifier backed by an environment value. This deliberately avoids adding a parameter to the five existing RouletteView / RouletteInternalView initializers.

RouletteView(parts: parts)
    .rouletteStyle(
        RouletteStyle(
            labelPosition: 0.8,        // 0 = centre, 1 = outer edge
            labelOrientation: .radial,
            innerRadiusRatio: 0.25     // hub size, 0 for a full pie
        )
    )

Parts render as annular sectors when a hub is configured and as full wedges otherwise, so the 1.x drawing path is untouched.

The default

The intent of #47 is a wheel that looks like a real roulette, so that is what the default is: labels out at the rim, laid out radially, hub in the middle.

	Default	.pie (1.x look)
labelPosition	0.74	0.5
labelOrientation	.radial	.tangential
innerRadiusRatio	0.22	0

As on a real wheel, labels on the left half sit upside down. That is the authentic arrangement rather than a defect, and it reads fine for numbers.

An earlier revision of this PR defaulted to .radialUpright, which flips that half to keep every label readable. Rendering the two side by side showed the flip reverses reading direction between neighbouring labels, which looks less coherent than the faithful layout — so the faithful one won the default and the flip stayed as an opt-in.

Every mode stays selectable

labelOrientation	Effect
.radial	Reads outward from the hub, exactly like a real roulette. The default.
.radialUpright	Same radial layout, left half flipped so every label reads upright. Better for word labels.
.tangential	Runs across the wedge, perpendicular to the radius. The 1.x behaviour.
.fixed	Always upright, whatever angle the wedge sits at.

// words rather than numbers
.rouletteStyle(RouletteStyle(labelOrientation: .radialUpright))

// the 1.x appearance, unchanged
.rouletteStyle(.pie)

Visual change

This changes the default appearance. Existing users will see labels move outward, rotate to follow their wedge, and a hub appear in the middle. That is the intent of #47, and it is why this belongs in the v2.0.0 major bump rather than a minor release. RouletteStyle.pie restores the previous look in one line.

Tests

Nine tests covering the default and .pie presets, ratio clamping, that all four orientations stay selectable, and the rotation maths for each — including the flip boundaries at 90°/270° and angles outside 0..<360. Geometry is pure logic, so it is unit-testable; the rendered result is not.

Not verified here

CI compiles the package and runs unit tests — it cannot tell whether the roulette looks right. The layout was checked by rasterising the same geometry maths outside SwiftUI, which validates label placement, rotation and hub size but not font metrics. Whether long labels such as "JavaScript" fit at the real system font size still wants a look in the demo app.