修复图片改造尺寸保持

保持图片改造提交与画布回填的原图尺寸
在 VectorEngine 边界对齐非 16 倍数参考图并恢复目标尺寸
补充前后端回归测试与编辑器尺寸契约文档

src/components/image-editor/ImageCanvasGenerationLayerModel.ts

@@ -247,18 +247,10 @@ export function applyImageEditResultToSourceLayer({
   sourceLayer: CanvasLayer;
   generationInputs: CanvasGenerationInputs;
 }): CanvasLayer {
-  const originalWidth =
-    generated.width || sourceLayer.originalWidth || sourceLayer.width;
-  const originalHeight =
-    generated.height || sourceLayer.originalHeight || sourceLayer.height;
-  const { width, height } = resolveLayerResolutionSize(
-    originalWidth,
-    originalHeight,
-    {
-      width: sourceLayer.width,
-      height: sourceLayer.height,
-    },
-  );
+  const originalWidth = sourceLayer.originalWidth || sourceLayer.width;
+  const originalHeight = sourceLayer.originalHeight || sourceLayer.height;
+  const width = sourceLayer.width;
+  const height = sourceLayer.height;
   return applyGeneratedMetadata(
     {
       ...sourceLayer,