🌐 add Argentine Spanish localization

[Texaliuz]

Hello, I would appreciate if you could add the translation to my language (es_ar) for version 1.21.1 please and thank you.

[opekope2]

Thanks for your contribution.
I'll add a lot more localization soon with the upcoming update.

[opekope2]

Hello!
Thank you for your patience — I was working on updating the translations, which took more time than I expected. I updated the translations on the dev branch with over 70 new translations.
If you want to submit updated translations for the next OptiGUI 3 alpha release, you have at least 30 days.

[Texaliuz]

All set, the translation is ready.

[opekope2]

After implementing more features, I had to make some minor changes to the translations.

After skimming through the translation file, I have some suggestions:

• optigui.rp_converter.convert_properties: OptiFine uses the .properties extension, but it can stay like how it is
• For optigui.rp_loader.warn.no_interaction_target, I didn't provide enough context. blocks, entities, items, inventory, and unknown will be part of V2 JSON resources (just like texture.PATH in OptiFine properties):

  {
    "blocks": [],
    "entities": [],
    "items": [],
    "inventory": false,
    "unknown": true
  }

[opekope2]

The translation keys for OptiGUI 3 alpha 4 are finished, no more additions, maybe small clarifications.
I organized the translation keys since your last revision, so some of them may be out of place. Other than that, 12 translations are missing.
You have at least 30 days to update your translation.

[opekope2]

LGTM, although I would change bloques, entidades, ítems, inventario, desconocido to blocks, entities, items, inventory, unknown, because that's how it appears in JSON, and I believe that resource pack creators would find it easier (see #157 (comment)).