Fix Cannot access offset of type array on array

[N1ebieski]

Fixes #340, #272, #262

If someone has an array in a .json translation file, something like this:

{
    "This is a correct translation": "To jest prawidłowe tłumaczenie",
    "This is not a correct translation": {
        "I don't know why people": "Nie wiem dlaczego ludzie",
        "do that": "robią coś takiego"
    }
}

then the extension throws an error:

2025-03-18 12:47:03.650 [error] Translations

Error: __VSCODE_LARAVEL_START_OUTPUT__
   TypeError 

  Cannot access offset of type array on array

  at vendor/_laravel_ide/discover-13e3a4436281ac748c1072dc641041d7.php:302
    298▕     }
    299▕ 
    300▕     protected function getValueIndex($value)
    301▕     {
  ➜ 302▕         $index = $this->values[$value] ?? null;
    303▕ 
    304▕         if ($index !== null) {
    305▕             return $index;
    306▕         }

This PR adds the extra check to verify if the translation is an array.

[mikebrandl]

I've got exactly the same issue as mentioned above.