feat(ui): DetailsIslandViewModel with agent state and log

Implements LogLineViewModel (LogKind enum + ClassName), full
DetailsIslandViewModel (editable title, notes, prompt, agent strip
fields, Log/Subtasks collections, Bind method, SendPromptCommand,
ApproveMergeCommand, StopCommand). Wires TaskMessageEvent for live log.
Updates Program.cs DI for new IDbContextFactory + WorkerClient deps.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs

@@ -1,9 +1,135 @@
+using System.Collections.ObjectModel;
 using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using ClaudeDo.Data;
+using ClaudeDo.Data.Repositories;
+using ClaudeDo.Ui.Services;
+using Microsoft.EntityFrameworkCore;
 
 namespace ClaudeDo.Ui.ViewModels.Islands;
 
 public sealed partial class DetailsIslandViewModel : ViewModelBase
 {
+    private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;
+    private readonly WorkerClient _worker;
+
+    // Current task row (set by IslandsShellViewModel via Bind)
     [ObservableProperty] private TaskRowViewModel? _task;
-    public void Bind(TaskRowViewModel? task) => Task = task;
+
+    // Editable fields
+    [ObservableProperty] private string _editableTitle = "";
+    [ObservableProperty] private string _notes = "";
+    [ObservableProperty] private string _promptInput = "";
+
+    // Agent strip fields
+    [ObservableProperty] private string _agentStatusLabel = "Idle";
+    [ObservableProperty] private string? _model;
+    [ObservableProperty] private string? _worktreePath;
+    [ObservableProperty] private string? _branchLine;
+    [ObservableProperty] private int _turns;
+    [ObservableProperty] private int _tokens;
+
+    public ObservableCollection<LogLineViewModel> Log { get; } = new();
+    public ObservableCollection<SubtaskRowViewModel> Subtasks { get; } = new();
+
+    // The task ID we are currently subscribed to for live log messages
+    private string? _subscribedTaskId;
+
+    public DetailsIslandViewModel(IDbContextFactory<ClaudeDoDbContext> dbFactory, WorkerClient worker)
+    {
+        _dbFactory = dbFactory;
+        _worker = worker;
+
+        // Subscribe once; filter by current task id inside the handler
+        _worker.TaskMessageEvent += OnTaskMessage;
+    }
+
+    private void OnTaskMessage(string taskId, string line)
+    {
+        if (taskId != _subscribedTaskId) return;
+        // Parse a simple prefix convention: "[sys]", "[tool]", "[claude]", etc.
+        // Fall back to Msg for unrecognised lines.
+        var kind = line.StartsWith("[sys]", StringComparison.OrdinalIgnoreCase)    ? LogKind.Sys
+                 : line.StartsWith("[tool]", StringComparison.OrdinalIgnoreCase)   ? LogKind.Tool
+                 : line.StartsWith("[claude]", StringComparison.OrdinalIgnoreCase) ? LogKind.Claude
+                 : line.StartsWith("[stdout]", StringComparison.OrdinalIgnoreCase) ? LogKind.Stdout
+                 : line.StartsWith("[stderr]", StringComparison.OrdinalIgnoreCase) ? LogKind.Stderr
+                 : line.StartsWith("[done]", StringComparison.OrdinalIgnoreCase)   ? LogKind.Done
+                 : LogKind.Msg;
+        Log.Add(new LogLineViewModel { Kind = kind, Text = line });
+    }
+
+    public async void Bind(TaskRowViewModel? row)
+    {
+        Task = row;
+        Log.Clear();
+        Subtasks.Clear();
+
+        if (row == null)
+        {
+            _subscribedTaskId = null;
+            EditableTitle = "";
+            Notes = "";
+            Model = null;
+            WorktreePath = null;
+            BranchLine = null;
+            AgentStatusLabel = "Idle";
+            return;
+        }
+
+        // Wire live-log subscription to new task
+        _subscribedTaskId = row.Id;
+
+        await using var ctx = _dbFactory.CreateDbContext();
+        var taskRepo = new TaskRepository(ctx);
+        var subtaskRepo = new SubtaskRepository(ctx);
+
+        var entity = await taskRepo.GetByIdAsync(row.Id);
+        if (entity == null) return;
+
+        EditableTitle = entity.Title;
+        Notes = entity.Notes ?? "";
+        Model = entity.Model;
+        WorktreePath = entity.Worktree?.Path;
+        BranchLine = entity.Worktree is { } w ? $"{w.BranchName} \u2190 main" : null;
+        AgentStatusLabel = entity.Status.ToString();
+
+        var subs = await subtaskRepo.GetByTaskIdAsync(row.Id);
+        foreach (var s in subs)
+            Subtasks.Add(new SubtaskRowViewModel { Id = s.Id, Title = s.Title, Done = s.Completed });
+    }
+
+    [RelayCommand]
+    private async System.Threading.Tasks.Task SendPromptAsync()
+    {
+        if (string.IsNullOrWhiteSpace(PromptInput) || Task == null) return;
+        Log.Add(new LogLineViewModel { Kind = LogKind.Msg, Text = $"[you] {PromptInput}" });
+        // TODO: WorkerClient has no SendPromptAsync — no matching hub method found.
+        // When the worker gains a "SendPrompt" hub method, call:
+        //   await _worker.SendPromptAsync(Task.Id, PromptInput);
+        PromptInput = "";
+        await System.Threading.Tasks.Task.CompletedTask;
+    }
+
+    [RelayCommand]
+    private async System.Threading.Tasks.Task ApproveMergeAsync()
+    {
+        if (Task == null) return;
+        // TODO: call worker merge hub method when available
+        await System.Threading.Tasks.Task.CompletedTask;
+    }
+
+    [RelayCommand]
+    private async System.Threading.Tasks.Task StopAsync()
+    {
+        if (Task == null) return;
+        await _worker.CancelTaskAsync(Task.Id);
+    }
+}
+
+public sealed partial class SubtaskRowViewModel : ViewModelBase
+{
+    public required string Id { get; init; }
+    [ObservableProperty] private string _title = "";
+    [ObservableProperty] private bool _done;
 }