feat(ui): session skills registry tab + per-level selectors

src/ClaudeDo.Ui/ViewModels/Agent/AgentConfigEditorViewModel.cs

@@ -1,4 +1,7 @@
 using System.Collections.ObjectModel;
+using System.Collections.Specialized;
+using System.ComponentModel;
+using System.Text.Json;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using ClaudeDo.Data.Models;
@@ -57,6 +60,7 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
 
     public ObservableCollection<string> ModelOptions { get; } = new(ModelRegistry.Aliases);
     public ObservableCollection<AgentInfo> Agents { get; } = new();
+    public ObservableCollection<SelectableSkillViewModel> SessionSkills { get; } = new();
 
     public AgentConfigEditorViewModel(IWorkerClient worker, AgentConfigScope scope)
     {
@@ -67,9 +71,31 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
         // short-lived modal recreated with the current language on each open.
         if (scope == AgentConfigScope.Task)
             Loc.LanguageChanged += _langChangedHandler;
+
+        SessionSkills.CollectionChanged += OnSessionSkillsCollectionChanged;
     }
 
-    public void Dispose() => Loc.LanguageChanged -= _langChangedHandler;
+    private void OnSessionSkillsCollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
+    {
+        if (e.NewItems is not null)
+            foreach (SelectableSkillViewModel item in e.NewItems)
+                item.PropertyChanged += OnSkillItemPropertyChanged;
+        if (e.OldItems is not null)
+            foreach (SelectableSkillViewModel item in e.OldItems)
+                item.PropertyChanged -= OnSkillItemPropertyChanged;
+    }
+
+    private void OnSkillItemPropertyChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (e.PropertyName == nameof(SelectableSkillViewModel.IsSelected)) QueueSave();
+    }
+
+    public void Dispose()
+    {
+        Loc.LanguageChanged -= _langChangedHandler;
+        SessionSkills.CollectionChanged -= OnSessionSkillsCollectionChanged;
+        foreach (var s in SessionSkills) s.PropertyChanged -= OnSkillItemPropertyChanged;
+    }
 
     partial void OnModelChanged(string? value) { RecomputeModelBadge(); QueueSave(); }
 
@@ -154,11 +180,18 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
         var sp = string.IsNullOrWhiteSpace(SystemPrompt) ? null : SystemPrompt;
         var ap = SelectedAgent is null || string.IsNullOrWhiteSpace(SelectedAgent.Path) ? null : SelectedAgent.Path;
         var turns = MaxTurns is decimal d ? (int?)d : null;
+        var skills = SelectedSessionSkillNames();
 
         if (_scope == AgentConfigScope.Task)
-            await _worker.UpdateTaskAgentSettingsAsync(new UpdateTaskAgentSettingsDto(TargetId, model, sp, ap, turns));
+            await _worker.UpdateTaskAgentSettingsAsync(new UpdateTaskAgentSettingsDto(TargetId, model, sp, ap, turns, skills));
         else
-            await _worker.UpdateListConfigAsync(new UpdateListConfigDto(TargetId, model, sp, ap, turns));
+            await _worker.UpdateListConfigAsync(new UpdateListConfigDto(TargetId, model, sp, ap, turns, skills));
+    }
+
+    private List<string>? SelectedSessionSkillNames()
+    {
+        var names = SessionSkills.Where(s => s.IsSelected).Select(s => s.Name).ToList();
+        return names.Count == 0 ? null : names;
     }
 
     public async System.Threading.Tasks.Task LoadForListAsync(string listId, CancellationToken ct = default)
@@ -172,6 +205,7 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
 
             var cfg = await _worker.GetListConfigAsync(listId);
             ApplyConfig(cfg?.Model, cfg?.MaxTurns, cfg?.SystemPrompt, cfg?.AgentPath);
+            await ReloadSessionSkillsAsync(cfg?.SessionSkills);
 
             _listModel = null; _listMaxTurns = null; _listAgentName = null;
             EffectiveSystemPromptHint = "";
@@ -189,6 +223,7 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
             TargetId = entity.Id;
             await ReloadAgentsAsync("(inherited)");
             ApplyConfig(entity.Model, entity.MaxTurns, entity.SystemPrompt, entity.AgentPath);
+            await ReloadSessionSkillsAsync(ParseSessionSkills(entity.SessionSkills));
 
             var listCfg = await _worker.GetListConfigAsync(entity.ListId);
             await LoadGlobalDefaultsAsync();
@@ -214,12 +249,30 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
             MaxTurns = null;
             SystemPrompt = "";
             SelectedAgent = null;
+            foreach (var s in SessionSkills) s.IsSelected = false;
         }
         finally { _suppressSave = false; }
         EffectiveSystemPromptHint = "";
         TargetId = null;
     }
 
+    private static List<string>? ParseSessionSkills(string? json)
+    {
+        if (string.IsNullOrWhiteSpace(json)) return null;
+        try { return JsonSerializer.Deserialize<List<string>>(json); }
+        catch (JsonException) { return null; }
+    }
+
+    private async System.Threading.Tasks.Task ReloadSessionSkillsAsync(IReadOnlyCollection<string>? selected)
+    {
+        var installed = await _worker.GetSessionSkillsAsync();
+        var selectedSet = selected is null ? new HashSet<string>() : new HashSet<string>(selected);
+        foreach (var s in SessionSkills) s.PropertyChanged -= OnSkillItemPropertyChanged;
+        SessionSkills.Clear();
+        foreach (var s in installed)
+            SessionSkills.Add(new SelectableSkillViewModel(s.Name, s.Description, selectedSet.Contains(s.Name)));
+    }
+
     private async System.Threading.Tasks.Task ReloadAgentsAsync(string placeholderName)
     {
         Agents.Clear();
@@ -255,5 +308,6 @@ public sealed partial class AgentConfigEditorViewModel : ViewModelBase, IDisposa
         MaxTurns = null;
         SystemPrompt = "";
         SelectedAgent = Agents.Count > 0 ? Agents[0] : null;
+        foreach (var s in SessionSkills) s.IsSelected = false;
     }
 }

src/ClaudeDo.Ui/ViewModels/Agent/SelectableSkillViewModel.cs

@@ -0,0 +1,23 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace ClaudeDo.Ui.ViewModels.Agent;
+
+/// <summary>
+/// One installed session skill shown as a checkbox row. Reused by the global (General tab),
+/// list, and task selectors — selection is additive-union across all three levels, so this
+/// is deliberately just a name + checked flag with no inheritance/override state.
+/// </summary>
+public sealed partial class SelectableSkillViewModel : ViewModelBase
+{
+    public string Name { get; }
+    public string Description { get; }
+
+    [ObservableProperty] private bool _isSelected;
+
+    public SelectableSkillViewModel(string name, string description = "", bool isSelected = false)
+    {
+        Name = name;
+        Description = description;
+        _isSelected = isSelected;
+    }
+}