style: 统一页面按钮样式与尺寸

src/components/Study.vue

@@ -457,12 +457,12 @@ onMounted(() => {
 
         <aside class="surface-card action-card">
           <div class="block-title">常用操作</div>
-          <el-button size="large" @click="fetchTasks" :loading="loading">刷新列表</el-button>
+          <el-button @click="fetchTasks" :loading="loading">刷新列表</el-button>
           <el-button type="success" size="large" @click="startTask">开始任务</el-button>
-          <el-button size="large" @click="addTask">添加任务</el-button>
-          <el-button size="large" @click="changeTask">更新任务</el-button>
-          <el-button size="large" @click="openWeightsDialog">权重配置</el-button>
-          <el-button type="danger" size="large" @click="removeTask">删除任务</el-button>
+          <el-button @click="addTask">添加任务</el-button>
+          <el-button @click="changeTask">更新任务</el-button>
+          <el-button @click="openWeightsDialog">权重配置</el-button>
+          <el-button type="danger" @click="removeTask">删除任务</el-button>
         </aside>
       </main>
     </div>