Add opt-in support for automatically annotating routes after migration tasks

[OdenTakashi]

Thank you as always for maintaining this project. I really appreciate your continued work.

This change introduces an opt-in feature that allows users to automatically annotate routes after running migration tasks. A new method, Runner.run_after_migration, has been added for this purpose, and the annotate_models_migrate.rake task has been updated to call this new method instead of invoking Runner.run(["models"]) directly.

The auto_annotate_routes_after_migrate option has been added to the Options class, enabling users to turn this behavior on by specifying auto_annotate_routes_after_migrate: true in their .annotaterb.yml. Corresponding tests have also been added.

Refs: #251