Update Neon colors and show color circles in theme picker

- Update NeonMoodTint to use synthwave colors matching Neon voting style
  (cyan, lime, yellow, orange, magenta)
- Replace text label with 5 color circles in theme preview Colors row
- Remove unused textColor customization code and picker views
- Add .id(moodTint) to Month/Year views for color refresh
- Clean up various unused color-related code

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Shared/Views/SwitchableView.swift

@@ -29,11 +29,9 @@ struct SwitchableView: View {
 
     @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
     @AppStorage(UserDefaultsStore.Keys.moodTint.rawValue, store: GroupUserDefaults.groupDefaults) private var moodTint: MoodTints = .Default
-    @AppStorage(UserDefaultsStore.Keys.textColor.rawValue, store: GroupUserDefaults.groupDefaults) private var textColor: Color = .white
-    
-    // store a value that gets changed when user updates custom colors to update the view since the moodTint doesn't change
-    @AppStorage(UserDefaultsStore.Keys.customMoodTintUpdateNumber.rawValue, store: GroupUserDefaults.groupDefaults) private var customMoodTintUpdateNumber: Int = 0
-    
+
+    private var textColor: Color { theme.currentTheme.labelColor }
+
     init(daysBack: Int, viewType: Binding<MainSwitchableViewType>, headerTypeChanged: @escaping ((MainSwitchableViewType) -> Void)) {
         self.daysBack = daysBack
         self.headerTypeChanged = headerTypeChanged
@@ -66,9 +64,6 @@ struct SwitchableView: View {
     var body: some View {
         VStack {
             ZStack {
-                Text(String(customMoodTintUpdateNumber))
-                    .hidden()
-                
                 mainViews
                     .padding([.top, .bottom])