Split home shortcut card style into Layout, Color, and Palette

Decouple the two concerns that were entangled in a single card-style setting:

- Layout (Compact / Regular) now only controls positioning of the
  icon / title / subtitle / counter.
- Color (Soft / Vibrant) is a new independent setting: Soft = tinted
  background with palette-colored icon and neutral text; Vibrant =
  solid palette fill with white icon/text.
- Palette (Accent first, then Classic/Sunset/Meadow/Berry/Grape/Custom)
  now applies to both layouts and both colors, and is always shown.

Adds section headers (Layout / Color / Palette) to the style page and
fixes the Compact preview to show the count subtitle line. Default is
Regular + Soft + Accent.

Yattee/Core/Settings/SettingsKey.swift

@@ -66,6 +66,7 @@ enum SettingsKey: String, CaseIterable {
     case homeShortcutVisibility
     case homeShortcutLayout
     case homeShortcutCardStyle
+    case homeShortcutCardColor
     case homeShortcutColorfulPalette
     case homeShortcutCustomPaletteColors
     case homeSectionOrder
@@ -141,7 +142,7 @@ enum SettingsKey: String, CaseIterable {
              .macPlayerSeparateWindow, .macPlayerFloating, .listStyle,
              // Home layout — different UI paradigms per platform
              .homeShortcutOrder, .homeShortcutVisibility, .homeShortcutLayout, .homeShortcutCardStyle,
-             .homeShortcutColorfulPalette, .homeShortcutCustomPaletteColors,
+             .homeShortcutCardColor, .homeShortcutColorfulPalette, .homeShortcutCustomPaletteColors,
              .homeSectionOrder, .homeSectionVisibility, .homeSectionItemsLimit, .homeSectionLayout,
              // Top Shelf — tvOS only
              .topShelfSections,

Yattee/Core/Settings/SettingsManager+Home.swift

@@ -95,14 +95,14 @@ extension SettingsManager {
         }
     }
 
-    /// Visual style for home shortcut cards (plain, accent-filled, or colorful). Default is plain.
+    /// Layout for home shortcut cards (compact or regular). Default is regular.
     var homeShortcutCardStyle: HomeShortcutCardStyle {
         get {
             if let cached = _homeShortcutCardStyle { return cached }
             guard let rawValue = string(for: .homeShortcutCardStyle) else {
-                return .plain
+                return .regular
             }
-            return HomeShortcutCardStyle(rawValue: rawValue) ?? .plain
+            return HomeShortcutCardStyle(rawValue: rawValue) ?? .regular
         }
         set {
             _homeShortcutCardStyle = newValue
@@ -110,15 +110,31 @@ extension SettingsManager {
         }
     }
 
-    /// Palette used by the "colorful" card style. Colors are applied by grid
-    /// position. Default is Classic.
+    /// Color emphasis for home shortcut cards (soft or vibrant), independent of
+    /// the layout style. Default is soft.
+    var homeShortcutCardColor: HomeShortcutCardColor {
+        get {
+            if let cached = _homeShortcutCardColor { return cached }
+            guard let rawValue = string(for: .homeShortcutCardColor) else {
+                return .soft
+            }
+            return HomeShortcutCardColor(rawValue: rawValue) ?? .soft
+        }
+        set {
+            _homeShortcutCardColor = newValue
+            set(newValue.rawValue, for: .homeShortcutCardColor)
+        }
+    }
+
+    /// Palette used by the "regular" card style. Colors are applied by grid
+    /// position. Default is Accent (the first palette option).
     var homeShortcutColorfulPalette: HomeShortcutColorfulPalette {
         get {
             if let cached = _homeShortcutColorfulPalette { return cached }
             guard let rawValue = string(for: .homeShortcutColorfulPalette) else {
-                return .classic
+                return .accent
             }
-            return HomeShortcutColorfulPalette(rawValue: rawValue) ?? .classic
+            return HomeShortcutColorfulPalette(rawValue: rawValue) ?? .accent
         }
         set {
             _homeShortcutColorfulPalette = newValue

Yattee/Core/SettingsManager.swift

@@ -110,6 +110,7 @@ final class SettingsManager {
     var _homeShortcutVisibility: [HomeShortcutItem: Bool]?
     var _homeShortcutLayout: HomeShortcutLayout?
     var _homeShortcutCardStyle: HomeShortcutCardStyle?
+    var _homeShortcutCardColor: HomeShortcutCardColor?
     var _homeShortcutColorfulPalette: HomeShortcutColorfulPalette?
     var _homeShortcutCustomPaletteColors: [String]?
     var _homeSectionOrder: [HomeSectionItem]?
@@ -469,6 +470,7 @@ final class SettingsManager {
         _homeShortcutVisibility = nil
         _homeShortcutLayout = nil
         _homeShortcutCardStyle = nil
+        _homeShortcutCardColor = nil
         _homeShortcutColorfulPalette = nil
         _homeShortcutCustomPaletteColors = nil
         _homeSectionOrder = nil