feat: support hyperparameters in distillation tuning

FUTURE_COPYBARA_INTEGRATE_REVIEW=#232 from googleapis:release-please--branches--main--components--Google.GenAI b8eaed6
PiperOrigin-RevId: 882708166

Author: speedstorm1

Google.GenAI/Tunings.cs

@@ -355,6 +355,11 @@ internal JsonNode CreateTuningJobConfigToVertex(JsonNode fromObject, JsonObject
           Common.SetValueByPath(parentObject, new string[] { "supervisedTuningSpec", "tuningMode" },
                                 Common.GetValueByPath(fromObject, new string[] { "tuningMode" }));
         }
+      } else if (discriminatorValueTuningMode == "DISTILLATION") {
+        if (Common.GetValueByPath(fromObject, new string[] { "tuningMode" }) != null) {
+          Common.SetValueByPath(parentObject, new string[] { "distillationSpec", "tuningMode" },
+                                Common.GetValueByPath(fromObject, new string[] { "tuningMode" }));
+        }
       }
       if (Common.GetValueByPath(fromObject, new string[] { "customBaseModel" }) != null) {
         Common.SetValueByPath(
@@ -373,6 +378,12 @@ internal JsonNode CreateTuningJobConfigToVertex(JsonNode fromObject, JsonObject
               parentObject, new string[] { "supervisedTuningSpec", "hyperParameters", "batchSize" },
               Common.GetValueByPath(fromObject, new string[] { "batchSize" }));
         }
+      } else if (discriminatorValueBatchSize == "DISTILLATION") {
+        if (Common.GetValueByPath(fromObject, new string[] { "batchSize" }) != null) {
+          Common.SetValueByPath(parentObject,
+                                new string[] { "distillationSpec", "hyperParameters", "batchSize" },
+                                Common.GetValueByPath(fromObject, new string[] { "batchSize" }));
+        }
       }
 
       JsonNode discriminatorLearningRate =
@@ -387,6 +398,12 @@ internal JsonNode CreateTuningJobConfigToVertex(JsonNode fromObject, JsonObject
               new string[] { "supervisedTuningSpec", "hyperParameters", "learningRate" },
               Common.GetValueByPath(fromObject, new string[] { "learningRate" }));
         }
+      } else if (discriminatorValueLearningRate == "DISTILLATION") {
+        if (Common.GetValueByPath(fromObject, new string[] { "learningRate" }) != null) {
+          Common.SetValueByPath(
+              parentObject, new string[] { "distillationSpec", "hyperParameters", "learningRate" },
+              Common.GetValueByPath(fromObject, new string[] { "learningRate" }));
+        }
       }
 
       if (Common.GetValueByPath(fromObject, new string[] { "labels" }) != null) {

Google.GenAI/types/CreateTuningJobConfig.cs

@@ -129,7 +129,7 @@ public AdapterSize
           }
 
     /// <summary>
-    /// Tuning mode for SFT tuning.
+    /// Tuning mode for tuning.
     /// </summary>
     [JsonPropertyName("tuningMode")]
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]

Google.GenAI/types/DistillationHyperParameters.cs

@@ -23,16 +23,36 @@
 
 namespace Google.GenAI.Types {
   /// <summary>
-  /// Hyperparameters for Distillation. This data type is not supported in Gemini API.
+  /// Hyperparameters for distillation.
   /// </summary>
 
   public record DistillationHyperParameters {
+    /// <summary>
+    /// The batch size hyperparameter for tuning. This is only supported for OSS models in Vertex.
+    /// </summary>
+    [JsonPropertyName("batchSize")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public int ? BatchSize { get; set; }
+
+    /// <summary>
+    /// The learning rate for tuning. OSS models only.
+    /// </summary>
+    [JsonPropertyName("learningRate")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public double
+        ? LearningRate {
+            get; set;
+          }
+
     /// <summary>
     /// Optional. Adapter size for distillation.
     /// </summary>
     [JsonPropertyName("adapterSize")]
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
-    public AdapterSize ? AdapterSize { get; set; }
+    public AdapterSize
+        ? AdapterSize {
+            get; set;
+          }
 
     /// <summary>
     /// Optional. Number of complete passes the model makes over the entire training dataset during

Google.GenAI/types/DistillationSpec.cs

@@ -35,13 +35,12 @@ public record DistillationSpec {
     public string ? PromptDatasetUri { get; set; }
 
     /// <summary>
-    /// The base teacher model that is being distilled. See Supported models
-    /// (https://cloud.google.com/vertex-ai/generative-ai/docs/model-reference/tuning#supported_models).
+    /// Tuning mode for tuning.
     /// </summary>
-    [JsonPropertyName("baseTeacherModel")]
+    [JsonPropertyName("tuningMode")]
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
-    public string
-        ? BaseTeacherModel {
+    public TuningMode
+        ? TuningMode {
             get; set;
           }
 
@@ -55,6 +54,17 @@ public DistillationHyperParameters
             get; set;
           }
 
+    /// <summary>
+    /// The base teacher model that is being distilled. See Supported models
+    /// (https://cloud.google.com/vertex-ai/generative-ai/docs/model-reference/tuning#supported_models).
+    /// </summary>
+    [JsonPropertyName("baseTeacherModel")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string
+        ? BaseTeacherModel {
+            get; set;
+          }
+
     /// <summary>
     /// Deprecated. A path in a Cloud Storage bucket, which will be treated as the root output
     /// directory of the distillation pipeline. It is used by the system to generate the paths of