feat(interactive): fresh-worktree-on-demand + ad-hoc launch specs

BuildForTaskAsync now creates a worktree on demand (via WorktreeManager.CreateAsync,
the same path TaskRunner uses) when a task has a configured working dir but no
Active/Kept worktree, returning a fresh-start spec -- so never-run tasks can be
opened interactively. Adds BuildForDirectoryAsync + GetAdHocLaunchSpec hub/client
for ad-hoc sessions in an arbitrary directory (no task, no worktree, no skill seeding).

src/ClaudeDo.Ui/Services/Interfaces/IWorkerClient.cs

@@ -90,6 +90,9 @@ public interface IWorkerClient : INotifyPropertyChanged
     /// <summary>Launch spec for an embedded ConPTY terminal to open an interactive session
     /// in a task's worktree (same worktree prep as an autonomous run).</summary>
     Task<LaunchSpec> GetInteractiveLaunchSpecAsync(string taskId, CancellationToken ct = default);
+    /// <summary>Launch spec for an ad-hoc interactive session in an arbitrary directory --
+    /// no task, no worktree.</summary>
+    Task<LaunchSpec> GetAdHocLaunchSpecAsync(string directory, CancellationToken ct = default);
     Task ResumePlanningSessionAsync(string taskId, CancellationToken ct = default);
     Task<DiscardPlanningOutcome> DiscardPlanningSessionAsync(string taskId, bool dequeueQueuedChildren = false, CancellationToken ct = default);
     Task FinalizePlanningSessionAsync(string taskId, bool queueAgentTasks = true, CancellationToken ct = default);

src/ClaudeDo.Ui/Services/WorkerClient.cs

@@ -567,6 +567,9 @@ public partial class WorkerClient : ObservableObject, IAsyncDisposable, IWorkerC
     public async Task<LaunchSpec> GetInteractiveLaunchSpecAsync(string taskId, CancellationToken ct = default)
         => await _hub.InvokeAsync<LaunchSpec>("GetInteractiveLaunchSpec", taskId, ct);
 
+    public async Task<LaunchSpec> GetAdHocLaunchSpecAsync(string directory, CancellationToken ct = default)
+        => await _hub.InvokeAsync<LaunchSpec>("GetAdHocLaunchSpec", directory, ct);
+
     public async Task<DiscardPlanningOutcome> DiscardPlanningSessionAsync(string taskId, bool dequeueQueuedChildren = false, CancellationToken ct = default)
         => await _hub.InvokeAsync<DiscardPlanningOutcome>("DiscardPlanningSessionAsync", taskId, dequeueQueuedChildren, ct);
 

src/ClaudeDo.Worker/Hub/WorkerHub.cs

@@ -671,6 +671,15 @@ public sealed class WorkerHub : Microsoft.AspNetCore.SignalR.Hub
         return _interactiveLaunchSpec.BuildForTaskAsync(taskId, Context.ConnectionAborted);
     });
 
+    // Builds the launch spec for an ad-hoc interactive session in an arbitrary directory --
+    // no task, no worktree, no session-skills seeding.
+    public Task<LaunchSpec> GetAdHocLaunchSpec(string directory) => HubGuard(() =>
+    {
+        if (_interactiveLaunchSpec is null)
+            throw new InvalidOperationException("Interactive launch spec service is not configured.");
+        return _interactiveLaunchSpec.BuildForDirectoryAsync(directory, Context.ConnectionAborted);
+    });
+
     public Task SendInteractiveMessage(string taskId, string text) =>
         _interactive.SendAsync(taskId, text, Context.ConnectionAborted);
 

src/ClaudeDo.Worker/Runner/InteractiveLaunchSpecService.cs

@@ -28,17 +28,20 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
     private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;
     private readonly ISessionSkillSeeder _skillSeeder;
     private readonly ISessionSkillRegistry _skillRegistry;
+    private readonly WorktreeManager _wtManager;
     private readonly string _claudePath;
 
     public InteractiveLaunchSpecService(
         IDbContextFactory<ClaudeDoDbContext> dbFactory,
         ISessionSkillSeeder skillSeeder,
         ISessionSkillRegistry skillRegistry,
+        WorktreeManager wtManager,
         WorkerConfig cfg)
     {
         _dbFactory = dbFactory;
         _skillSeeder = skillSeeder;
         _skillRegistry = skillRegistry;
+        _wtManager = wtManager;
         _claudePath = cfg.ClaudeBin;
     }
 
@@ -52,14 +55,32 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
             throw new InvalidOperationException("Can't open an interactive session for a running or queued task -- interrupt it first.");
 
         var worktree = await new WorktreeRepository(ctx).GetByTaskIdAsync(taskId, ct);
+        var isFreshWorktree = false;
+
         if (worktree is null || worktree.State is not (WorktreeState.Active or WorktreeState.Kept))
-            throw new InvalidOperationException("This task has no active worktree to open a session in.");
-        if (!Directory.Exists(worktree.Path))
+        {
+            // No usable worktree yet -- if the task's list points at a git repo, create one
+            // on demand via the SAME mechanism an autonomous run uses (WorktreeManager.CreateAsync:
+            // branch naming, base commit resolution, worktree-root strategy, DB registration).
+            var list = await new ListRepository(ctx).GetByIdAsync(task.ListId, ct);
+            if (list?.WorkingDir is null)
+                throw new InvalidOperationException("This task has no working directory configured -- can't create a worktree.");
+
+            await _wtManager.CreateAsync(task, list, ct);
+            worktree = await new WorktreeRepository(ctx).GetByTaskIdAsync(taskId, ct)
+                ?? throw new InvalidOperationException("Worktree creation did not persist a worktree row.");
+            isFreshWorktree = true;
+        }
+        else if (!Directory.Exists(worktree.Path))
+        {
             throw new InvalidOperationException("The task's worktree directory no longer exists.");
+        }
 
         var listConfig = await new ListRepository(ctx).GetConfigAsync(task.ListId, ct);
         var globalSettings = await new AppSettingsRepository(ctx).GetAsync(ct);
-        var run = await new TaskRunRepository(ctx).GetLatestByTaskIdAsync(taskId, ct);
+        // A brand-new worktree has no prior session to resume, regardless of any session
+        // history the task accumulated before its previous worktree went away.
+        var run = isFreshWorktree ? null : await new TaskRunRepository(ctx).GetLatestByTaskIdAsync(taskId, ct);
 
         var requestedSkills = TaskRunner.UnionSkillNames(task.SessionSkills, listConfig?.SessionSkills, globalSettings.SessionSkills);
         var skillNames = await FilterToInstalledSkillsAsync(requestedSkills, ct);
@@ -83,6 +104,22 @@ public sealed class InteractiveLaunchSpecService : IInteractiveLaunchSpecService
         return new LaunchSpec(worktree.Path, resolvedClaude, args, env);
     }
 
+    public Task<LaunchSpec> BuildForDirectoryAsync(string directory, CancellationToken ct)
+    {
+        if (!Directory.Exists(directory))
+            throw new InvalidOperationException($"Directory does not exist: {directory}");
+
+        var resolvedClaude = WindowsTerminalLauncher.Resolve(_claudePath)
+            ?? throw new InvalidOperationException($"claude executable not found: {_claudePath}");
+
+        var env = new Dictionary<string, string>
+        {
+            ["MCP_TOOL_TIMEOUT"] = "200000",
+        };
+
+        return Task.FromResult(new LaunchSpec(directory, resolvedClaude, Array.Empty<string>(), env));
+    }
+
     private async Task<IReadOnlyList<string>> FilterToInstalledSkillsAsync(IReadOnlyList<string> requested, CancellationToken ct)
     {
         if (requested.Count == 0) return requested;

src/ClaudeDo.Worker/Runner/Interfaces/IInteractiveLaunchSpecService.cs

@@ -2,9 +2,17 @@ namespace ClaudeDo.Worker.Runner;
 
 public interface IInteractiveLaunchSpecService
 {
-    /// <summary>Builds a LaunchSpec for opening an interactive session in an existing task's
-    /// worktree. Throws KeyNotFoundException if the task doesn't exist, InvalidOperationException
-    /// if it's Running/Queued or has no usable worktree. A task that has never run (no persisted
-    /// SessionId) is not an error -- the spec omits --resume for a fresh start.</summary>
+    /// <summary>Builds a LaunchSpec for opening an interactive session in a task's worktree.
+    /// Throws KeyNotFoundException if the task doesn't exist, InvalidOperationException
+    /// if it's Running/Queued. If the task has no usable worktree yet, one is created on
+    /// demand (same mechanism as an autonomous run) provided the task's list has a working
+    /// directory pointing at a git repo -- otherwise throws InvalidOperationException. A task
+    /// that has never run, or whose worktree was just created fresh, gets a fresh-start spec
+    /// (no --resume); an existing worktree with a persisted SessionId gets --resume.</summary>
     Task<LaunchSpec> BuildForTaskAsync(string taskId, CancellationToken ct);
+
+    /// <summary>Builds a LaunchSpec for an ad-hoc interactive session in an arbitrary directory --
+    /// no task, no worktree, no session-skills seeding. Throws InvalidOperationException if the
+    /// directory doesn't exist.</summary>
+    Task<LaunchSpec> BuildForDirectoryAsync(string directory, CancellationToken ct);
 }

tests/ClaudeDo.Ui.Tests/StubWorkerClient.cs

@@ -107,6 +107,8 @@ public abstract class StubWorkerClient : IWorkerClient
     public virtual Task ResumeTaskInTerminalAsync(string taskId, CancellationToken ct = default) => Task.CompletedTask;
     public virtual Task<LaunchSpec> GetInteractiveLaunchSpecAsync(string taskId, CancellationToken ct = default)
         => Task.FromResult(new LaunchSpec(".", "claude", Array.Empty<string>(), new Dictionary<string, string>()));
+    public virtual Task<LaunchSpec> GetAdHocLaunchSpecAsync(string directory, CancellationToken ct = default)
+        => Task.FromResult(new LaunchSpec(directory, "claude", Array.Empty<string>(), new Dictionary<string, string>()));
     public virtual Task ResumePlanningSessionAsync(string taskId, CancellationToken ct = default) => Task.CompletedTask;
     public virtual Task<DiscardPlanningOutcome> DiscardPlanningSessionAsync(string taskId, bool dequeueQueuedChildren = false, CancellationToken ct = default)
         => Task.FromResult(new DiscardPlanningOutcome(DiscardPlanningResult.Discarded, 0, 0));

tests/ClaudeDo.Worker.Tests/Runner/InteractiveLaunchSpecServiceTests.cs

@@ -1,9 +1,11 @@
+using ClaudeDo.Data.Git;
 using ClaudeDo.Data.Models;
 using ClaudeDo.Data.Repositories;
 using ClaudeDo.Worker.Config;
 using ClaudeDo.Worker.Runner;
 using ClaudeDo.Worker.Skills;
 using ClaudeDo.Worker.Tests.Infrastructure;
+using Microsoft.Extensions.Logging.Abstractions;
 using TaskStatus = ClaudeDo.Data.Models.TaskStatus;
 
 namespace ClaudeDo.Worker.Tests.Runner;
@@ -21,6 +23,9 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
     private readonly string _claudeStubPath;
     private readonly FakeSessionSkillSeeder _seeder = new();
     private readonly FakeSessionSkillRegistry _registry = new();
+    private readonly List<GitRepoFixture> _gitFixtures = new();
+
+    private static bool GitAvailable => GitRepoFixture.IsGitAvailable();
 
     public InteractiveLaunchSpecServiceTests()
     {
@@ -34,9 +39,17 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
         File.WriteAllText(_claudeStubPath, "stub");
     }
 
+    private GitRepoFixture CreateRepo()
+    {
+        var f = new GitRepoFixture();
+        _gitFixtures.Add(f);
+        return f;
+    }
+
     public void Dispose()
     {
         _db.Dispose();
+        foreach (var f in _gitFixtures) f.Dispose();
         try { Directory.Delete(_tempDir, true); } catch { /* best effort */ }
     }
 
@@ -52,15 +65,17 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
     }
 
     private InteractiveLaunchSpecService BuildService() =>
-        new(_db.CreateFactory(), _seeder, _registry, new WorkerConfig { ClaudeBin = _claudeStubPath });
+        new(_db.CreateFactory(), _seeder, _registry,
+            new WorktreeManager(new GitService(), _db.CreateFactory(), new WorkerConfig(), NullLogger<WorktreeManager>.Instance),
+            new WorkerConfig { ClaudeBin = _claudeStubPath });
 
-    private async Task<string> SeedListAsync()
+    private async Task<string> SeedListAsync(string? workingDir = null)
     {
         var listId = Guid.NewGuid().ToString();
         using var ctx = _db.CreateContext();
         await new ListRepository(ctx).AddAsync(new ListEntity
         {
-            Id = listId, Name = "L", WorkingDir = _tempDir, CreatedAt = DateTime.UtcNow,
+            Id = listId, Name = "L", WorkingDir = workingDir ?? _tempDir, CreatedAt = DateTime.UtcNow,
         });
         return listId;
     }
@@ -122,7 +137,7 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
     }
 
     [Fact]
-    public async Task BuildForTaskAsync_NoWorktreeRow_ThrowsInvalidOperation()
+    public async Task BuildForTaskAsync_NoWorktreeRow_NotAGitRepo_ThrowsInvalidOperation()
     {
         var listId = await SeedListAsync();
         var taskId = Guid.NewGuid().ToString();
@@ -133,6 +148,43 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
             () => svc.BuildForTaskAsync(taskId, CancellationToken.None));
     }
 
+    [Fact]
+    public async Task BuildForTaskAsync_NoWorktreeRow_NoWorkingDirConfigured_ThrowsInvalidOperation()
+    {
+        var listId = await SeedListAsync(workingDir: null);
+        var taskId = Guid.NewGuid().ToString();
+        await SeedTaskAsync(taskId, listId, TaskStatus.Idle);
+
+        var svc = BuildService();
+        await Assert.ThrowsAsync<InvalidOperationException>(
+            () => svc.BuildForTaskAsync(taskId, CancellationToken.None));
+    }
+
+    [Fact]
+    public async Task BuildForTaskAsync_FreshTask_NoWorktreeButGitRepoConfigured_CreatesWorktreeOnDemand()
+    {
+        if (!GitAvailable) { Assert.True(true, "git not available -- skipping"); return; }
+
+        var repo = CreateRepo();
+        var listId = await SeedListAsync(workingDir: repo.RepoDir);
+        var taskId = Guid.NewGuid().ToString();
+        await SeedTaskAsync(taskId, listId, TaskStatus.Idle);
+        // No worktree row seeded -- task has never run.
+
+        var svc = BuildService();
+        var spec = await svc.BuildForTaskAsync(taskId, CancellationToken.None);
+
+        using var readCtx = _db.CreateContext();
+        var wtRow = await new WorktreeRepository(readCtx).GetByTaskIdAsync(taskId);
+        Assert.NotNull(wtRow);
+        Assert.Equal(WorktreeState.Active, wtRow!.State);
+        Assert.True(Directory.Exists(wtRow.Path));
+
+        Assert.Equal(wtRow.Path, spec.Cwd);
+        Assert.Empty(spec.Args);
+        Assert.Equal(_claudeStubPath, spec.Exe);
+    }
+
     [Theory]
     [InlineData(WorktreeState.Merged)]
     [InlineData(WorktreeState.Discarded)]
@@ -249,4 +301,25 @@ public sealed class InteractiveLaunchSpecServiceTests : IDisposable
         Assert.True(call.IsWorktree);
         Assert.Equal(new[] { "installed-skill" }, call.SkillNames);
     }
+
+    [Fact]
+    public async Task BuildForDirectoryAsync_ExistingDirectory_ReturnsFreshStartSpec()
+    {
+        var svc = BuildService();
+        var spec = await svc.BuildForDirectoryAsync(_tempDir, CancellationToken.None);
+
+        Assert.Equal(_tempDir, spec.Cwd);
+        Assert.Equal(_claudeStubPath, spec.Exe);
+        Assert.Empty(spec.Args);
+        Assert.Equal("200000", spec.Env["MCP_TOOL_TIMEOUT"]);
+        Assert.Empty(_seeder.Calls);
+    }
+
+    [Fact]
+    public async Task BuildForDirectoryAsync_NonExistentDirectory_ThrowsInvalidOperation()
+    {
+        var svc = BuildService();
+        await Assert.ThrowsAsync<InvalidOperationException>(
+            () => svc.BuildForDirectoryAsync(Path.Combine(_tempDir, "does-not-exist"), CancellationToken.None));
+    }
 }

tests/ClaudeDo.Worker.Tests/UiVm/TasksIslandViewModelPlanningTests.cs

@@ -79,6 +79,8 @@ sealed class FakeWorkerClient : IWorkerClient
     public Task ResumeTaskInTerminalAsync(string taskId, CancellationToken ct = default) { PickUpInTerminalCalls++; LastPickUpTaskId = taskId; return Task.CompletedTask; }
     public Task<LaunchSpec> GetInteractiveLaunchSpecAsync(string taskId, CancellationToken ct = default)
         => Task.FromResult(new LaunchSpec(".", "claude", Array.Empty<string>(), new Dictionary<string, string>()));
+    public Task<LaunchSpec> GetAdHocLaunchSpecAsync(string directory, CancellationToken ct = default)
+        => Task.FromResult(new LaunchSpec(directory, "claude", Array.Empty<string>(), new Dictionary<string, string>()));
     public Task QueuePlanningSubtasksAsync(string parentTaskId, CancellationToken ct = default) => Task.CompletedTask;
     public Task ResumePlanningSessionAsync(string taskId, CancellationToken ct = default) { ResumePlanningCalls++; return Task.CompletedTask; }
     public Task<DiscardPlanningOutcome> DiscardPlanningSessionAsync(string taskId, bool dequeueQueuedChildren = false, CancellationToken ct = default)