style(提交列表): 翻上一条下一条只用 ↑ ↓，去掉 ← →

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/oj/submission/components/FlowchartPane.vue

@@ -258,7 +258,7 @@ const canRetry = computed(
     </div>
 
     <div v-if="!narrow" class="foot">
-      <span class="keys"><kbd>↑</kbd><kbd>↓</kbd><kbd>←</kbd><kbd>→</kbd></span>
+      <span class="keys"><kbd>↑</kbd><kbd>↓</kbd></span>
       <span>换上一张 / 下一张</span>
       <div class="spacer"></div>
       <span v-if="position">本页第 {{ position.index }} / {{ position.count }} 条</span>

apps/web/src/oj/submission/components/SubmissionPane.vue

@@ -398,7 +398,7 @@ function openStandalone() {
     </template>
 
     <div v-if="!narrow" class="foot">
-      <span class="keys"><kbd>↑</kbd><kbd>↓</kbd><kbd>←</kbd><kbd>→</kbd></span>
+      <span class="keys"><kbd>↑</kbd><kbd>↓</kbd></span>
       <span>
         {{
           teacher