Update image-to-image target size param docstring (#1788)

Related to huggingface/huggingface_hub#3399,
some providers or models may ignore this parameter if it's not
supported. This PR updates the docstring to make that clearer and align
it with the one in `huggingface_hub`.

Author: hanouticelina

packages/tasks/src/tasks/image-to-image/inference.ts

@@ -41,13 +41,15 @@ export interface ImageToImageParameters {
 	 */
 	prompt?: string;
 	/**
-	 * The size in pixel of the output image.
+	 * The size in pixels of the output image. This parameter is only supported by some
+	 * providers and for specific models. It will be ignored when unsupported.
 	 */
 	target_size?: TargetSize;
 	[property: string]: unknown;
 }
 /**
- * The size in pixel of the output image.
+ * The size in pixels of the output image. This parameter is only supported by some
+ * providers and for specific models. It will be ignored when unsupported.
  */
 export interface TargetSize {
 	height: number;

packages/tasks/src/tasks/image-to-image/spec/input.json

@@ -38,7 +38,7 @@
 				},
 				"target_size": {
 					"type": "object",
-					"description": "The size in pixel of the output image.",
+					"description": "The size in pixels of the output image. This parameter is only supported by some providers and for specific models. It will be ignored when unsupported.",
 					"properties": {
 						"width": {
 							"type": "integer"