feat(data): persist max_turns in list and task repositories

Add MaxTurns to ListRepository.SetConfigAsync upsert branch and
TaskRepository.UpdateAgentSettingsAsync; fix positional CancellationToken
call in ConfigMcpTools. Covered by MaxTurnsRoundTripTests (2 tests).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ClaudeDo.Data/Repositories/ListRepository.cs

@@ -65,6 +65,7 @@ public sealed class ListRepository
             existing.Model = config.Model;
             existing.SystemPrompt = config.SystemPrompt;
             existing.AgentPath = config.AgentPath;
+            existing.MaxTurns = config.MaxTurns;
         }
         await _context.SaveChangesAsync(ct);
     }

src/ClaudeDo.Data/Repositories/TaskRepository.cs

@@ -159,6 +159,7 @@ public sealed class TaskRepository
         string? model,
         string? systemPrompt,
         string? agentPath,
+        int? maxTurns = null,
         CancellationToken ct = default)
     {
         await _context.Tasks
@@ -166,7 +167,8 @@ public sealed class TaskRepository
             .ExecuteUpdateAsync(s => s
                 .SetProperty(t => t.Model, model)
                 .SetProperty(t => t.SystemPrompt, systemPrompt)
-                .SetProperty(t => t.AgentPath, agentPath), ct);
+                .SetProperty(t => t.AgentPath, agentPath)
+                .SetProperty(t => t.MaxTurns, maxTurns), ct);
     }
 
     #endregion

src/ClaudeDo.Worker/External/ConfigMcpTools.cs

@@ -58,7 +58,7 @@ public sealed class ConfigMcpTools
         _ = await _tasks.GetByIdAsync(taskId, cancellationToken)
             ?? throw new InvalidOperationException($"Task {taskId} not found.");
 
-        await _tasks.UpdateAgentSettingsAsync(taskId, model.NullIfBlank(), systemPrompt.NullIfBlank(), agentPath.NullIfBlank(), cancellationToken);
+        await _tasks.UpdateAgentSettingsAsync(taskId, model.NullIfBlank(), systemPrompt.NullIfBlank(), agentPath.NullIfBlank(), ct: cancellationToken);
         await _broadcaster.TaskUpdated(taskId);
     }
 }

tests/ClaudeDo.Worker.Tests/Repositories/MaxTurnsRoundTripTests.cs

@@ -0,0 +1,79 @@
+using ClaudeDo.Data;
+using ClaudeDo.Data.Models;
+using ClaudeDo.Data.Repositories;
+using ClaudeDo.Worker.Tests.Infrastructure;
+
+namespace ClaudeDo.Worker.Tests.Repositories;
+
+public sealed class MaxTurnsRoundTripTests : IDisposable
+{
+    private readonly DbFixture _db = new();
+
+    public void Dispose() => _db.Dispose();
+
+    [Fact]
+    public async Task ListConfig_persists_max_turns()
+    {
+        var listId = Guid.NewGuid().ToString();
+        using (var ctx = _db.CreateContext())
+        {
+            await new ListRepository(ctx).AddAsync(new ListEntity
+            {
+                Id = listId, Name = "L", CreatedAt = DateTime.UtcNow,
+            });
+        }
+
+        using (var ctx = _db.CreateContext())
+        {
+            await new ListRepository(ctx).SetConfigAsync(new ListConfigEntity
+            {
+                ListId = listId, MaxTurns = 42,
+            });
+        }
+
+        using var readCtx = _db.CreateContext();
+        var config = await new ListRepository(readCtx).GetConfigAsync(listId);
+        Assert.NotNull(config);
+        Assert.Equal(42, config!.MaxTurns);
+    }
+
+    [Fact]
+    public async Task Task_agent_settings_persist_and_clear_max_turns()
+    {
+        var listId = Guid.NewGuid().ToString();
+        var taskId = Guid.NewGuid().ToString();
+        using (var ctx = _db.CreateContext())
+        {
+            await new ListRepository(ctx).AddAsync(new ListEntity
+            {
+                Id = listId, Name = "L", CreatedAt = DateTime.UtcNow,
+            });
+            await new TaskRepository(ctx).AddAsync(new TaskEntity
+            {
+                Id = taskId, ListId = listId, Title = "t", CreatedAt = DateTime.UtcNow,
+            });
+        }
+
+        using (var ctx = _db.CreateContext())
+        {
+            await new TaskRepository(ctx).UpdateAgentSettingsAsync(taskId, null, null, null, maxTurns: 7);
+        }
+
+        using (var ctx = _db.CreateContext())
+        {
+            var entity = await new TaskRepository(ctx).GetByIdAsync(taskId);
+            Assert.NotNull(entity);
+            Assert.Equal(7, entity!.MaxTurns);
+        }
+
+        using (var ctx = _db.CreateContext())
+        {
+            await new TaskRepository(ctx).UpdateAgentSettingsAsync(taskId, null, null, null, maxTurns: null);
+        }
+
+        using var readCtx = _db.CreateContext();
+        var final = await new TaskRepository(readCtx).GetByIdAsync(taskId);
+        Assert.NotNull(final);
+        Assert.Null(final!.MaxTurns);
+    }
+}