import export support + hide default pattern category

I request to add two useful features to your plugin.

1. Import Export feature, so that we can export pattern created in one site and then can import it in another site. Like this plugin provide for reusable block https://www.ads-software.com/plugins/reusable-blocks-extended/

2. Some setting option to hide all default categories and pattern that show when we go to choose pattern in WordPress page editor, this way only show our custom patterns created with this plugin. For more clear explanation see screenshot https://prnt.sc/Iy1q76sPloCL