UnlockCard styles

Control unlock card appearance, including header, key button, progress, instructions, and status states.

Used by SeamUnlockCardView and related UI (container, header, key button, progress, instructions, status colors).

public struct UnlockCard {
    // Container & header
    public var cardBackground: Color?
    public var headerBackground: Color?
    public var dividerColor: Color
    public var headerTitleColor: Color
    public var headerSubtitleColor: Color
    public var providerLogoTint: Color

    // Primary action (big key)
    public var keyIconColorIdle: Color
    public var keyIconColorActive: Color
    public var keyButtonGradient: [Color]
    public var keyButtonShadowColor: Color
    public var keyButtonShadowRadius: CGFloat
    public var keyButtonShadowYOffset: CGFloat

    // Progress & labels
    public var progressColor: Color
    public var phaseTitleColor: Color

    // Instructions
    public var instructionTextColor: Color
    public var bulletBackground: Color
    public var bulletTextColor: Color

    // Status
    public var successColor: Color
    public var errorColor: Color
    public var statusMessageColor: Color
}

Examples:

// Subtle gradient and soft shadow for the big key button
let unlock = SeamTheme.UnlockCard.default.with(
    keyButtonGradient: [Color.accentColor.opacity(0.75), .accentColor],
    keyButtonShadowColor: .black.opacity(0.12),
    keyButtonShadowRadius: 10,
    keyButtonShadowYOffset: 6,
    progressColor: .accentColor
)

// Dark header with light title/subtitle
let darkHeader = SeamTheme.UnlockCard.default.with(
    headerBackground: .black,
    headerTitleColor: .white,
    headerSubtitleColor: .white.opacity(0.7),
    providerLogoTint: .white.opacity(0.8)
)