feat(ui): accent color presets in Settings → General

Adds Moss / Peat / Sea preset swatches to the General settings tab.
Selecting a preset mutates the live SolidColorBrush objects in the
Application resource dictionary so all StaticResource consumers update
instantly; the choice is persisted to ui.config.json and re-applied
at startup. Missing or unknown saved value falls back to Moss.

src/ClaudeDo.App/App.axaml.cs

@@ -3,6 +3,7 @@ using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
+using ClaudeDo.Ui;
 using ClaudeDo.Ui.Services;
 using ClaudeDo.Ui.ViewModels;
 using ClaudeDo.Ui.Views;
@@ -22,6 +23,8 @@ public partial class App : Application
     public override void Initialize()
     {
         AvaloniaXamlLoader.Load(this);
+        if (_services?.GetService<AppSettings>() is { } settings)
+            AccentPresetService.Apply(AccentPresets.Find(settings.AccentPreset));
     }
 
     public override void OnFrameworkInitializationCompleted()

src/ClaudeDo.Localization/locales/de.json

@@ -31,7 +31,11 @@
       "weekdayFriday": "Freitag",
       "weekdaySaturday": "Samstag",
       "sessionSkills": "Session-Skills",
-      "sessionSkillsHint": "Gilt für jede Aufgabe. Kombiniert sich mit Listen- und Aufgaben-Auswahl."
+      "sessionSkillsHint": "Gilt für jede Aufgabe. Kombiniert sich mit Listen- und Aufgaben-Auswahl.",
+      "accentPreset": "Akzentfarbe",
+      "accentPresetMoss": "Moos",
+      "accentPresetPeat": "Torf",
+      "accentPresetSea": "Meer"
     },
     "worktrees": {
       "strategy": "Strategie",

src/ClaudeDo.Localization/locales/en.json

@@ -31,7 +31,11 @@
       "weekdayFriday": "Friday",
       "weekdaySaturday": "Saturday",
       "sessionSkills": "Session skills",
-      "sessionSkillsHint": "Applied to every task. Combines with list- and task-level selections."
+      "sessionSkillsHint": "Applied to every task. Combines with list- and task-level selections.",
+      "accentPreset": "Accent color",
+      "accentPresetMoss": "Moss",
+      "accentPresetPeat": "Peat",
+      "accentPresetSea": "Sea"
     },
     "worktrees": {
       "strategy": "Strategy",

src/ClaudeDo.Ui/AccentPresets.cs

@@ -0,0 +1,43 @@
+using Avalonia.Media;
+using ClaudeDo.Ui.Localization;
+using ClaudeDo.Ui.ViewModels;
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace ClaudeDo.Ui;
+
+public sealed record AccentPreset(string Name, string Accent, string Dim, string Soft, string Glow);
+
+public static class AccentPresets
+{
+    // Hue 88 — moss/sage green (original)
+    public static readonly AccentPreset Moss = new("moss", "#FF7C9166", "#FF64785A", "#FF3E4B39", "#387C9166");
+    // Hue ~40 — warm earthy brown/terra
+    public static readonly AccentPreset Peat = new("peat", "#FF9A7B5C", "#FF7F6449", "#FF4D3C2C", "#389A7B5C");
+    // Hue ~180 — cool teal/sea-green
+    public static readonly AccentPreset Sea  = new("sea",  "#FF5B8F8C", "#FF4A7573", "#FF263D3C", "#385B8F8C");
+
+    public static readonly IReadOnlyList<AccentPreset> All = [Moss, Peat, Sea];
+    public static AccentPreset Default => Moss;
+
+    public static AccentPreset Find(string? name) =>
+        All.FirstOrDefault(p => p.Name == name) ?? Default;
+}
+
+public sealed partial class AccentPresetSwatchViewModel : ViewModelBase
+{
+    public AccentPreset Preset { get; }
+
+    [ObservableProperty] private bool _isSelected;
+
+    public Color DisplayColor { get; }
+
+    public string DisplayName =>
+        Loc.T($"settings.general.accentPreset{char.ToUpperInvariant(Preset.Name[0])}{Preset.Name.Substring(1)}");
+
+    public AccentPresetSwatchViewModel(AccentPreset preset, bool selected)
+    {
+        Preset = preset;
+        _isSelected = selected;
+        DisplayColor = Color.Parse(preset.Accent);
+    }
+}

src/ClaudeDo.Ui/AppSettings.cs

@@ -8,6 +8,7 @@ public sealed class AppSettings
     public string DbPath { get; set; } = "~/.todo-app/todo.db";
     public string SignalRUrl { get; set; } = "http://127.0.0.1:47821/hub";
     public string Language { get; set; } = "";
+    public string AccentPreset { get; set; } = "";
 
     private static readonly string ConfigPath = Paths.Expand("~/.todo-app/ui.config.json");
 

src/ClaudeDo.Ui/Services/AccentPresetService.cs

@@ -0,0 +1,24 @@
+using Avalonia;
+using Avalonia.Media;
+
+namespace ClaudeDo.Ui.Services;
+
+public static class AccentPresetService
+{
+    public static void Apply(AccentPreset preset)
+    {
+        if (Application.Current is not { } app) return;
+
+        SetBrushColor(app, "AccentBrush",     preset.Accent);
+        SetBrushColor(app, "AccentDimBrush",  preset.Dim);
+        SetBrushColor(app, "AccentSoftBrush", preset.Soft);
+        SetBrushColor(app, "AccentGlowBrush", preset.Glow);
+        SetBrushColor(app, "MossBrush",       preset.Accent);
+    }
+
+    private static void SetBrushColor(Application app, string key, string hex)
+    {
+        if (app.TryGetResource(key, null, out var value) && value is SolidColorBrush brush)
+            brush.Color = Color.Parse(hex);
+    }
+}

src/ClaudeDo.Ui/ViewModels/Modals/Settings/GeneralSettingsTabViewModel.cs

@@ -4,6 +4,7 @@ using ClaudeDo.Localization;
 using ClaudeDo.Ui.Services;
 using ClaudeDo.Ui.ViewModels.Agent;
 using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
 
 namespace ClaudeDo.Ui.ViewModels.Modals.Settings;
 
@@ -27,6 +28,27 @@ public sealed partial class GeneralSettingsTabViewModel : ViewModelBase
 
     public ObservableCollection<SelectableSkillViewModel> SessionSkills { get; } = new();
 
+    public ObservableCollection<AccentPresetSwatchViewModel> AccentPresetSwatches { get; } = new();
+    private Action<string>? _persistAccent;
+
+    public void InitAccentPresets(string saved, Action<string> persist)
+    {
+        _persistAccent = persist;
+        var current = AccentPresets.Find(saved);
+        AccentPresetSwatches.Clear();
+        foreach (var p in AccentPresets.All)
+            AccentPresetSwatches.Add(new AccentPresetSwatchViewModel(p, p.Name == current.Name));
+    }
+
+    [RelayCommand]
+    private void SelectAccentPreset(AccentPreset preset)
+    {
+        foreach (var s in AccentPresetSwatches)
+            s.IsSelected = s.Preset.Name == preset.Name;
+        AccentPresetService.Apply(preset);
+        _persistAccent?.Invoke(preset.Name);
+    }
+
     /// <summary>One editable row per model alias: the effort and turn budget a run gets under that
     /// model. Supplies the global defaults; list- and task-level max-turns overrides still win.</summary>
     public ObservableCollection<ModelPresetRowViewModel> ModelPresets { get; } = new();

src/ClaudeDo.Ui/ViewModels/Modals/SettingsModalViewModel.cs

@@ -36,6 +36,11 @@ public sealed partial class SettingsModalViewModel : ViewModelBase
             appSettings.Language = code;
             appSettings.Save();
         });
+        General.InitAccentPresets(appSettings.AccentPreset, preset =>
+        {
+            appSettings.AccentPreset = preset;
+            appSettings.Save();
+        });
         Worktrees = new WorktreesSettingsTabViewModel(worker);
         Files = new FilesSettingsTabViewModel(worker);
         Prime = prime;

src/ClaudeDo.Ui/Views/Modals/SettingsModalView.axaml

@@ -2,6 +2,7 @@
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:vm="using:ClaudeDo.Ui.ViewModels.Modals"
         xmlns:settings="using:ClaudeDo.Ui.ViewModels.Modals.Settings"
+        xmlns:ui="using:ClaudeDo.Ui"
         xmlns:agent="using:ClaudeDo.Ui.ViewModels.Agent"
         xmlns:services="using:ClaudeDo.Ui.Services"
         xmlns:ctl="using:ClaudeDo.Ui.Views.Controls"
@@ -61,6 +62,39 @@
                   </ComboBox.ItemTemplate>
                 </ComboBox>
               </StackPanel>
+              <StackPanel Spacing="4">
+                <TextBlock Classes="field-label" Text="{loc:Tr settings.general.accentPreset}"/>
+                <ItemsControl ItemsSource="{Binding General.AccentPresetSwatches}">
+                  <ItemsControl.ItemsPanel>
+                    <ItemsPanelTemplate>
+                      <StackPanel Orientation="Horizontal" Spacing="8"/>
+                    </ItemsPanelTemplate>
+                  </ItemsControl.ItemsPanel>
+                  <ItemsControl.ItemTemplate>
+                    <DataTemplate x:DataType="ui:AccentPresetSwatchViewModel">
+                      <Button Padding="6,4"
+                              Command="{Binding $parent[ItemsControl].((vm:SettingsModalViewModel)DataContext).General.SelectAccentPresetCommand}"
+                              CommandParameter="{Binding Preset}">
+                        <StackPanel Spacing="4">
+                          <Grid Width="32" Height="32">
+                            <Border Width="32" Height="32" CornerRadius="16"
+                                    BorderBrush="{DynamicResource AccentBrush}" BorderThickness="2"
+                                    IsVisible="{Binding IsSelected}"/>
+                            <Ellipse Width="22" Height="22"
+                                     HorizontalAlignment="Center" VerticalAlignment="Center">
+                              <Ellipse.Fill>
+                                <SolidColorBrush Color="{Binding DisplayColor}"/>
+                              </Ellipse.Fill>
+                            </Ellipse>
+                          </Grid>
+                          <TextBlock Text="{Binding DisplayName}"
+                                     HorizontalAlignment="Center" FontSize="11"/>
+                        </StackPanel>
+                      </Button>
+                    </DataTemplate>
+                  </ItemsControl.ItemTemplate>
+                </ItemsControl>
+              </StackPanel>
               <StackPanel Spacing="4">
                 <TextBlock Classes="field-label" Text="{loc:Tr settings.general.defaultInstructions}"/>
                 <TextBox AcceptsReturn="True" TextWrapping="Wrap" Height="110"