feat(mcp): add per-run TaskRunTokenRegistry

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

@@ -0,0 +1,36 @@
+using ClaudeDo.Worker.Runner;
+using Xunit;
+
+namespace ClaudeDo.Worker.Tests.Runner;
+
+public sealed class TaskRunTokenRegistryTests
+{
+    [Fact]
+    public void Register_then_resolve_returns_taskId()
+    {
+        var reg = new TaskRunTokenRegistry();
+        reg.Register("tok", "task-1");
+        Assert.True(reg.TryResolve("tok", out var id));
+        Assert.Equal("task-1", id);
+    }
+
+    [Fact]
+    public void Unregister_removes_token()
+    {
+        var reg = new TaskRunTokenRegistry();
+        reg.Register("tok", "task-1");
+        reg.Unregister("tok");
+        Assert.False(reg.TryResolve("tok", out _));
+    }
+
+    [Fact]
+    public void GenerateToken_is_urlsafe_and_unique()
+    {
+        var a = TaskRunTokenRegistry.GenerateToken();
+        var b = TaskRunTokenRegistry.GenerateToken();
+        Assert.NotEqual(a, b);
+        Assert.DoesNotContain('+', a);
+        Assert.DoesNotContain('/', a);
+        Assert.DoesNotContain('=', a);
+    }
+}