Deterministic title placeholder painter

Items without artwork need better than a shared grey square: something unique per item, identical every time, and available synchronously — before, during and instead of a network load. Hashing the title into a gradient gives all three; a Painter lets the loader treat it as an image.

// adapted
private fun gradientFromTitle(title: String): List<Color> {
    val hash = title.hashCode()
    val hue1 = ((hash and 0xFF) / 255f) * 360f
    val hue2 = (((hash shr 8) and 0xFF) / 255f) * 360f
    return listOf(hsvToColor(hue1, 0.7f, 0.9f), hsvToColor(hue2, 0.7f, 0.85f))
}