Update TypeSpec emitter version to prerelease 1.0.0-alpha.20250912.2

eng/azure-typespec-http-client-csharp-emitter-package.json

@@ -1,7 +1,7 @@
 {
   "main": "dist/src/index.js",
   "dependencies": {
-    "@azure-typespec/http-client-csharp": "1.0.0-alpha.20250911.2"
+    "@azure-typespec/http-client-csharp": "1.0.0-alpha.20250912.2"
   },
   "devDependencies": {
     "@azure-tools/typespec-azure-core": "0.60.0",

sdk/ai/Azure.AI.VoiceLive/api/Azure.AI.VoiceLive.net8.0.cs

@@ -1406,7 +1406,6 @@ internal SessionUpdateResponseAnimationVisemeDone() { }
         public string ResponseId { get { throw null; } }
         protected override Azure.AI.VoiceLive.SessionUpdate JsonModelCreateCore(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         protected override void JsonModelWriteCore(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
-        public static explicit operator Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone (Azure.Response result) { throw null; }
         protected override Azure.AI.VoiceLive.SessionUpdate PersistableModelCreateCore(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         protected override System.BinaryData PersistableModelWriteCore(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone System.ClientModel.Primitives.IJsonModel<Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }

sdk/ai/Azure.AI.VoiceLive/api/Azure.AI.VoiceLive.netstandard2.0.cs

@@ -1406,7 +1406,6 @@ internal SessionUpdateResponseAnimationVisemeDone() { }
         public string ResponseId { get { throw null; } }
         protected override Azure.AI.VoiceLive.SessionUpdate JsonModelCreateCore(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         protected override void JsonModelWriteCore(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
-        public static explicit operator Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone (Azure.Response result) { throw null; }
         protected override Azure.AI.VoiceLive.SessionUpdate PersistableModelCreateCore(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         protected override System.BinaryData PersistableModelWriteCore(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone System.ClientModel.Primitives.IJsonModel<Azure.AI.VoiceLive.SessionUpdateResponseAnimationVisemeDone>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }