Convert this Python code to idiomatic Rust. The code must compile, handle errors properly, and follow Rust best practices. ```python from dataclasses import dataclass from typing import Optional, List from datetime import datetime @dataclass class Task: id: int title: str completed: bool due_date: Optional[datetime] tags: List[str] class TaskManager: def __init__(self): self.tasks = [] self.next_id = 1 def add_task(self, title: str, due_date: Optional[datetime] = None, tags: List[str] = None) -> Task: task = Task( id=self.next_id, title=title, completed=False, due_date=due_date, tags=tags or [] ) self.tasks.append(task) self.next_id += 1 return task def complete_task(self, task_id: int) -> bool: for task in self.tasks: if task.id == task_id: task.completed = True return True return False def get_overdue(self) -> List[Task]: now = datetime.now() return [t for t in self.tasks if t.due_date and t.due_date < now and not t.completed] ```