feat: [Translate] Add supported fields in document translation request and refresh translation v3 GA service proto documentation

Translate/samples/V3/TranslationServiceClient/batch_translate_document.php

@@ -50,10 +50,10 @@
  *                                           the same location-id) can be used, otherwise an INVALID_ARGUMENT (400)
  *                                           error is returned. Please see
  *                                           {@see TranslationServiceClient::locationName()} for help formatting this field.
- * @param string $sourceLanguageCode         The BCP-47 language code of the input document if known, for
+ * @param string $sourceLanguageCode         The ISO-639 language code of the input document if known, for
  *                                           example, "en-US" or "sr-Latn". Supported language codes are listed in
- *                                           Language Support (https://cloud.google.com/translate/docs/languages).
- * @param string $targetLanguageCodesElement The BCP-47 language code to use for translation of the input
+ *                                           [Language Support](https://cloud.google.com/translate/docs/languages).
+ * @param string $targetLanguageCodesElement The ISO-639 language code to use for translation of the input
  *                                           document. Specify up to 10 language codes here.
  */
 function batch_translate_document_sample(

Translate/samples/V3/TranslationServiceClient/translate_document.php

@@ -43,7 +43,7 @@
  *
  *                                   Models and glossaries must be within the same region (have the same
  *                                   location-id), otherwise an INVALID_ARGUMENT (400) error is returned.
- * @param string $targetLanguageCode The BCP-47 language code to use for translation of the input
+ * @param string $targetLanguageCode The ISO-639 language code to use for translation of the input
  *                                   document, set to one of the language codes listed in Language Support.
  */
 function translate_document_sample(string $parent, string $targetLanguageCode): void

Translate/samples/V3/TranslationServiceClient/translate_text.php

@@ -31,10 +31,9 @@
  * Translates input text and returns translated text.
  *
  * @param string $contentsElement    The content of the input in string format.
- *                                   We recommend the total content be less than 30k codepoints. The max length
- *                                   of this field is 1024.
- *                                   Use BatchTranslateText for larger text.
- * @param string $targetLanguageCode The BCP-47 language code to use for translation of the input
+ *                                   We recommend the total content be less than 30,000 codepoints. The max
+ *                                   length of this field is 1024. Use BatchTranslateText for larger text.
+ * @param string $targetLanguageCode The ISO-639 language code to use for translation of the input
  *                                   text, set to one of the language codes listed in Language Support.
  * @param string $formattedParent    Project or location to make a call. Must refer to a caller's
  *                                   project.