createTask method
Create a working task and store it. Returns the Task handle whose
Task.toCreateTaskResult a tools/call (or other) handler can return so
the client tracks it via tasks/get. Server-directed per the spec.
Implementation
Task createTask({String? statusMessage, int? ttlMs, int? pollIntervalMs}) {
final now = _nowIso();
final task = Task(
taskId: Uuid().v4(),
status: TaskStatus.working,
createdAt: now,
lastUpdatedAt: now,
statusMessage: statusMessage,
ttlMs: ttlMs,
pollIntervalMs: pollIntervalMs,
);
_tasks[task.taskId] = task;
return task;
}