feat: [discoveryengine] add Natural Language Query Understanding fields and messages to DiscoveryEngine request, response, and datastore messages

packages/google-cloud-discoveryengine/protos/google/cloud/discoveryengine/v1/data_store.proto

@@ -1,4 +1,4 @@
-// Copyright 2025 Google LLC
+// Copyright 2026 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -132,6 +132,11 @@ message DataStore {
   AdvancedSiteSearchConfig advanced_site_search_config = 12
       [(google.api.field_behavior) = OPTIONAL];
 
+  // Optional. Configuration for Natural Language Query Understanding.
+  NaturalLanguageQueryUnderstandingConfig
+      natural_language_query_understanding_config = 34
+      [(google.api.field_behavior) = OPTIONAL];
+
   // Input only. The KMS key to be used to protect this DataStore at creation
   // time.
   //
@@ -223,6 +228,30 @@ message AdvancedSiteSearchConfig {
   optional bool disable_automatic_refresh = 4;
 }
 
+// Configuration for Natural Language Query Understanding.
+message NaturalLanguageQueryUnderstandingConfig {
+  // Mode of Natural Language Query Understanding. When the
+  // NaturalLanguageQueryUnderstandingConfig.Mode is ENABLED, the natural
+  // language understanding capabilities will be enabled for a search request if
+  // the NaturalLanguageQueryUnderstandingSpec.FilterExtractionCondition in the
+  // SearchRequest is ENABLED.
+  enum Mode {
+    // Default value.
+    MODE_UNSPECIFIED = 0;
+
+    // Natural Language Query Understanding is disabled.
+    DISABLED = 1;
+
+    // Natural Language Query Understanding is enabled.
+    ENABLED = 2;
+  }
+
+  // Mode of Natural Language Query Understanding. If this field is unset, the
+  // behavior defaults to
+  // [NaturalLanguageQueryUnderstandingConfig.Mode.DISABLED][google.cloud.discoveryengine.v1.NaturalLanguageQueryUnderstandingConfig.Mode.DISABLED].
+  Mode mode = 1;
+}
+
 // Config to store data store type configuration for workspace data
 message WorkspaceConfig {
   // Specifies the type of Workspace App supported by this DataStore