Add stay/follow option for pets

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• Migrations have been added if applicable
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This merge request adds the option to tell your pet to stay or follow you. When your pet is told to stay it will wonder about using idle tree as if it wasn't tamed, then you can tell it to follow and it will follow you as normal. This is my first time programming in rust so I almost defiantly have missed something or done things in an unconventional way, so please let me know what I need to improve!

Thanks!!