feat(texttospeech): update the API

#### texttospeech:v1beta1

The following keys were added:
- schemas.VoiceSelectionParams.properties.modelName.description
- schemas.VoiceSelectionParams.properties.modelName.type

#### texttospeech:v1

The following keys were added:
- schemas.VoiceSelectionParams.properties.modelName.description
- schemas.VoiceSelectionParams.properties.modelName.type

Author: yoshi-automation

discovery/texttospeech-v1.json

@@ -318,7 +318,7 @@
       }
     }
   },
-  "revision": "20250716",
+  "revision": "20250805",
   "rootUrl": "https://texttospeech.googleapis.com/",
   "schemas": {
     "AdvancedVoiceOptions": {
@@ -791,6 +791,10 @@
           "description": "Required. The language (and potentially also the region) of the voice expressed as a [BCP-47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt) language tag, e.g. \"en-US\". This should not include a script tag (e.g. use \"cmn-cn\" rather than \"cmn-Hant-cn\"), because the script will be inferred from the input provided in the SynthesisInput. The TTS service will use this parameter to help choose an appropriate voice. Note that the TTS service may choose a voice with a slightly different language code than the one selected; it may substitute a different region (e.g. using en-US rather than en-CA if there isn't a Canadian voice available), or even a different language, e.g. using \"nb\" (Norwegian Bokmal) instead of \"no\" (Norwegian)\".",
           "type": "string"
         },
+        "modelName": {
+          "description": "Optional. The name of the model. If set, the service will choose the model matching the specified configuration.",
+          "type": "string"
+        },
         "name": {
           "description": "The name of the voice. If both the name and the gender are not set, the service will choose a voice based on the other parameters such as language_code.",
           "type": "string"

discovery/texttospeech-v1beta1.json

@@ -261,7 +261,7 @@
       }
     }
   },
-  "revision": "20250716",
+  "revision": "20250805",
   "rootUrl": "https://texttospeech.googleapis.com/",
   "schemas": {
     "AdvancedVoiceOptions": {
@@ -766,6 +766,10 @@
           "description": "Required. The language (and potentially also the region) of the voice expressed as a [BCP-47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt) language tag, e.g. \"en-US\". This should not include a script tag (e.g. use \"cmn-cn\" rather than \"cmn-Hant-cn\"), because the script will be inferred from the input provided in the SynthesisInput. The TTS service will use this parameter to help choose an appropriate voice. Note that the TTS service may choose a voice with a slightly different language code than the one selected; it may substitute a different region (e.g. using en-US rather than en-CA if there isn't a Canadian voice available), or even a different language, e.g. using \"nb\" (Norwegian Bokmal) instead of \"no\" (Norwegian)\".",
           "type": "string"
         },
+        "modelName": {
+          "description": "Optional. The name of the model. If set, the service will choose the model matching the specified configuration.",
+          "type": "string"
+        },
         "name": {
           "description": "The name of the voice. If both the name and the gender are not set, the service will choose a voice based on the other parameters such as language_code.",
           "type": "string"

src/apis/texttospeech/v1.ts

@@ -453,6 +453,10 @@ export namespace texttospeech_v1 {
      * Required. The language (and potentially also the region) of the voice expressed as a [BCP-47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt) language tag, e.g. "en-US". This should not include a script tag (e.g. use "cmn-cn" rather than "cmn-Hant-cn"), because the script will be inferred from the input provided in the SynthesisInput. The TTS service will use this parameter to help choose an appropriate voice. Note that the TTS service may choose a voice with a slightly different language code than the one selected; it may substitute a different region (e.g. using en-US rather than en-CA if there isn't a Canadian voice available), or even a different language, e.g. using "nb" (Norwegian Bokmal) instead of "no" (Norwegian)".
      */
     languageCode?: string | null;
+    /**
+     * Optional. The name of the model. If set, the service will choose the model matching the specified configuration.
+     */
+    modelName?: string | null;
     /**
      * The name of the voice. If both the name and the gender are not set, the service will choose a voice based on the other parameters such as language_code.
      */

src/apis/texttospeech/v1beta1.ts

@@ -468,6 +468,10 @@ export namespace texttospeech_v1beta1 {
      * Required. The language (and potentially also the region) of the voice expressed as a [BCP-47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt) language tag, e.g. "en-US". This should not include a script tag (e.g. use "cmn-cn" rather than "cmn-Hant-cn"), because the script will be inferred from the input provided in the SynthesisInput. The TTS service will use this parameter to help choose an appropriate voice. Note that the TTS service may choose a voice with a slightly different language code than the one selected; it may substitute a different region (e.g. using en-US rather than en-CA if there isn't a Canadian voice available), or even a different language, e.g. using "nb" (Norwegian Bokmal) instead of "no" (Norwegian)".
      */
     languageCode?: string | null;
+    /**
+     * Optional. The name of the model. If set, the service will choose the model matching the specified configuration.
+     */
+    modelName?: string | null;
     /**
      * The name of the voice. If both the name and the gender are not set, the service will choose a voice based on the other parameters such as language_code.
      */