修复图标描述回退与移动端重复样式

修正图标生成恢复时空提示词对旧描述的阻断。

删除移动端生成按钮重复的宽度声明。

src/components/image-editor/ImageCanvasGenerationDialogModel.ts

@@ -909,8 +909,7 @@ function restoreIconDescriptionsFromLayer(
 ): Omit<CanvasGenerationDialogState, 'id'> {
   const prompt =
     findGenerationInputFieldValue(sourceLayer, ['素材描述']) ??
-    sourceDialog?.prompt ??
-    sourceDialog?.iconDescriptions?.join('\n') ??
+    (sourceDialog?.prompt || sourceDialog?.iconDescriptions?.join('\n')) ??
     '';
   const normalizedPrompt = prompt.trim();
   return {

src/index.css

@@ -8945,10 +8945,6 @@ button.image-canvas-editor__reference-chip:disabled {
     justify-content: flex-start;
   }
 
-  .image-canvas-editor__generation-submit {
-    width: 100%;
-  }
-
   .image-canvas-editor__character-composer {
     position: fixed;
     left: 0.75rem !important;