Make plugin translation ready

[dutchigor]

All text is already written using the WordPress translation function (__) but the project needs to be set up to load translations from the marketplace.

See:

• https://developer.wordpress.org/plugins/internationalization/how-to-internationalize-your-plugin/
• https://developer.wordpress.org/block-editor/how-to-guides/internationalization/

[dutchigor]

From documentation:

• Text domain must be the same as the plugin slug
• Remove domain path
• Add text domain to all translatable strings
• Add call to wp_set_script_translations in init to load js translations for the admin page script. The block translations should be loaded automatically.