chore: Release library Google.Cloud.AIPlatform.V1Beta1 version 1.0.0-beta66

### New features

- RAG - add mode config to RagEngineConfig with Spanner and Serverless
- RAG - deprecate tier from RagEngineConfig

### Documentation improvements

- A comment for message `RagManagedDbConfig` is changed
- A comment for field `scaled` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed
- A comment for field `basic` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed
- A comment for field `unprovisioned` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed

Librarian-Release-Library: Google.Cloud.AIPlatform.V1Beta1
Librarian-Release-Version: 1.0.0-beta66
Librarian-Release-ID: release-20260126T140114Z

Author: google-cloud-sdk-librarian-dotnet-robot

apis/Google.Cloud.AIPlatform.V1Beta1/Google.Cloud.AIPlatform.V1Beta1/Google.Cloud.AIPlatform.V1Beta1.csproj

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <Version>1.0.0-beta65</Version>
+    <Version>1.0.0-beta66</Version>
     <TargetFrameworks>netstandard2.0;net462</TargetFrameworks>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <Description>Recommended Google client library to access the Vertex AI API (v1beta), which allows you to train high-quality custom machine learning models with minimal machine learning expertise and effort.</Description>

apis/Google.Cloud.AIPlatform.V1Beta1/docs/history.md

@@ -1,5 +1,19 @@
 # Version history
 
+## Version 1.0.0-beta66, released 2026-01-26
+
+### New features
+
+- RAG - add mode config to RagEngineConfig with Spanner and Serverless
+- RAG - deprecate tier from RagEngineConfig
+
+### Documentation improvements
+
+- A comment for message `RagManagedDbConfig` is changed
+- A comment for field `scaled` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed
+- A comment for field `basic` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed
+- A comment for field `unprovisioned` in message `.google.cloud.aiplatform.v1beta1.RagManagedDbConfig` is changed
+
 ## Version 1.0.0-beta65, released 2026-01-08
 
 ### New features

generator-input/apis.json

@@ -412,7 +412,7 @@
     },
     {
       "id": "Google.Cloud.AIPlatform.V1Beta1",
-      "version": "1.0.0-beta65",
+      "version": "1.0.0-beta66",
       "type": "grpc",
       "productName": "Vertex AI",
       "productUrl": "https://cloud.google.com/vertex-ai/docs",

generator-input/pipeline-state.json

@@ -273,12 +273,12 @@
         },
         {
             "id": "Google.Cloud.AIPlatform.V1Beta1",
-            "currentVersion": "1.0.0-beta65",
+            "currentVersion": "1.0.0-beta66",
             "generationAutomationLevel": "AUTOMATION_LEVEL_AUTOMATIC",
             "releaseAutomationLevel": "AUTOMATION_LEVEL_AUTOMATIC",
-            "releaseTimestamp": "2026-01-08T08:25:10.872615366Z",
+            "releaseTimestamp": "2026-01-26T14:05:21.873694874Z",
             "lastGeneratedCommit": "87e3579c041a50f985f8de71e9494c8fc85d520b",
-            "lastReleasedCommit": "286c66a565ed6d9cfecb062e7ac13363e76f2e0a",
+            "lastReleasedCommit": "87e3579c041a50f985f8de71e9494c8fc85d520b",
             "apiPaths": [
                 "google/cloud/aiplatform/v1beta1"
             ],