fix: 优化移动端工作台筛选与工具栏

将形态图片状态筛选合并为下拉框，统一筛选容器内边距并调整背景。重新排列分镜与镜头生产移动端工具栏，隐藏重复统计并补充交互测试。

src/features/storyboard/StoryboardPage.vue

@@ -468,6 +468,21 @@ watch(
     @apply p-0;
 }
 @media (max-width: 760px) {
+    /* 移动端按整行排列剧集、统计和操作，避免 flex 自动换行留下不规则空白。 */
+    .storyboard-workspace-page .workspace-toolbar {
+        @apply grid grid-cols-[minmax(0,_1fr)] gap-2;
+    }
+    .storyboard-workspace-page .toolbar-episode,
+    .storyboard-workspace-page .toolbar-metrics,
+    .storyboard-workspace-page .toolbar-actions {
+        @apply w-full min-w-0 m-0;
+    }
+    .storyboard-workspace-page .toolbar-metrics {
+        @apply justify-between;
+    }
+    .storyboard-workspace-page .toolbar-actions {
+        @apply justify-start;
+    }
     .storyboard-workspace {
         @apply grid-cols-[minmax(0,_1fr)] grid-rows-[184px_minmax(0,_1fr)];
     }