feat!: change GenerateImageConfig.NumberOfImages to value type. And add clearer error message and docstring to other APIs.

PiperOrigin-RevId: 734589810

Author: qiaodev

models.go

@@ -52,7 +52,7 @@ func generateImage(ctx context.Context) {
 	}
 	// Pass in basic config
 	var config *genai.GenerateImagesConfig = &genai.GenerateImagesConfig{
-		NumberOfImages:   genai.Ptr[int64](1),
+		NumberOfImages:   1,
 		OutputMIMEType:   "image/jpeg",
 		IncludeRAIReason: true,
 	}

samples/generate_images.go

@@ -67,8 +67,6 @@ func imagen(ctx context.Context) {
 		ctx, "imagen-3.0-generate-002",
 		/*prompt=*/ "An umbrella in the foreground, and a rainy night sky in the background",
 		&genai.GenerateImagesConfig{
-			// TODO: Change this to value type.
-			NumberOfImages:   genai.Ptr[int64](1),
 			IncludeRAIReason: true,
 			OutputMIMEType:   "image/jpeg",
 		},
@@ -101,7 +99,7 @@ func imagen(ctx context.Context) {
 		ReferenceID: 2,
 		Config: &genai.MaskReferenceConfig{
 			MaskMode:     "MASK_MODE_BACKGROUND",
-			MaskDilation: genai.Ptr(0.0),
+			MaskDilation: genai.Ptr[float32](0.0),
 		},
 	}
 	response3, err := client.Models.EditImage(