Fix interface implementation issues in MediaPipe tasks-genai binding

Co-authored-by: mattleibow <1096616+mattleibow@users.noreply.github.com>

Author: Copilot

source/com.google.mediapipe/tasks-genai/Additions/LlmOptionsProto.cs

@@ -0,0 +1,35 @@
+using System;
+
+namespace Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto
+{
+    public sealed partial class LlmOptionsProto
+    {
+        public partial class LlmModelSettings : global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.ILlmModelSettingsOrBuilder
+        {
+            // Explicit interface implementations to fix the missing interface members
+            global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.LlmModelSettings.LlmPreferredBackend? ILlmModelSettingsOrBuilder.LlmPreferredBackend
+            {
+                get => GetLlmPreferredBackend();
+            }
+            
+            global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.LlmModelSettings.VisionModelSettings? ILlmModelSettingsOrBuilder.VisionModelSettings
+            {
+                get => GetVisionModelSettings();
+            }
+        }
+        
+        public partial class LlmSessionConfig : global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.ILlmSessionConfigOrBuilder
+        {
+            // Explicit interface implementations to fix the missing interface members  
+            global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.LlmSessionConfig.GraphConfig? ILlmSessionConfigOrBuilder.GraphConfig
+            {
+                get => GetGraphConfig();
+            }
+            
+            global::Google.Mediapipe.Tasks.Genai.Llminference.Jni.Proto.LlmOptionsProto.LlmSessionConfig.PromptTemplates? ILlmSessionConfigOrBuilder.PromptTemplates
+            {
+                get => GetPromptTemplates();
+            }
+        }
+    }
+}