feat(worker): resolve max-turns from task then list then global default

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

src/ClaudeDo.Worker/Runner/TaskRunner.cs

@@ -390,10 +390,13 @@ public sealed class TaskRunner
             SystemPrompt: string.IsNullOrWhiteSpace(instructions) ? null : instructions,
             AgentPath: task.AgentPath ?? listConfig?.AgentPath,
             ResumeSessionId: resumeSessionId,
-            MaxTurns: global.DefaultMaxTurns,
+            MaxTurns: ResolveMaxTurns(task.MaxTurns, listConfig?.MaxTurns, global.DefaultMaxTurns),
             PermissionMode: global.DefaultPermissionMode);
     }
 
+    internal static int? ResolveMaxTurns(int? taskTurns, int? listTurns, int globalDefault)
+        => taskTurns ?? listTurns ?? globalDefault;
+
     public static string MergeInstructions(params string?[] parts)
     {
         var trimmed = parts

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

@@ -0,0 +1,19 @@
+using ClaudeDo.Worker.Runner;
+using Xunit;
+
+namespace ClaudeDo.Worker.Tests.Runner;
+
+public class MaxTurnsResolutionTests
+{
+    [Fact]
+    public void Task_override_wins()
+        => Assert.Equal(5, TaskRunner.ResolveMaxTurns(taskTurns: 5, listTurns: 20, globalDefault: 100));
+
+    [Fact]
+    public void List_override_used_when_no_task_override()
+        => Assert.Equal(20, TaskRunner.ResolveMaxTurns(taskTurns: null, listTurns: 20, globalDefault: 100));
+
+    [Fact]
+    public void Falls_back_to_global_default()
+        => Assert.Equal(100, TaskRunner.ResolveMaxTurns(taskTurns: null, listTurns: null, globalDefault: 100));
+}