style(loading-manage): 调整变更备注输入框行数及卡片最小高度

- 设置变更备注输入框默认显示2行，提升输入体验
- 为 section-card 添加最小高度限制，防止内容过少时布局过紧
- 注释掉无用样式，保持代码整洁

src/views/business/loading-manage.vue

@@ -957,7 +957,7 @@
             </el-table>
           </section-card>
           <section-card title="路线编辑"><template #extra><span class="loading-route-change-dialog__hint">拖拽调整顺序</span></template><div v-if="routeChangeNodes.length" class="loading-route-change-dialog__route-list"><div v-for="(node, index) in routeChangeNodes" :key="node.key || index" class="loading-route-change-dialog__route-item" draggable="true" @dragstart="handleRouteChangeDragStart(index)" @dragover.prevent @drop="handleRouteChangeDrop(index)"><span :class="['loading-route-change-dialog__route-type', `loading-route-change-dialog__route-type--${routeChangeTypeClass(index)}`]">{{ routeChangeTypeText(index) }}</span><span>{{ node.address }}</span><span class="loading-route-change-dialog__tags"><el-tag v-for="tag in node.tags || []" :key="tag" size="small">{{ tag }}</el-tag></span><el-icon><Rank /></el-icon></div></div><el-empty v-else description="暂无路线" :image-size="60" /></section-card>
-          <el-form label-width="auto"><el-form-item label="变更备注"><el-input v-model="routeChangeRemark" type="textarea" :rows="" maxlength="200" show-word-limit placeholder="请输入" /></el-form-item></el-form>
+          <el-form label-width="auto"><el-form-item label="变更备注"><el-input v-model="routeChangeRemark" type="textarea" :rows="2" maxlength="200" show-word-limit placeholder="请输入" /></el-form-item></el-form>
         </el-tab-pane>
         <el-tab-pane label="变更记录" name="records"><el-table :data="routeChangeRecords" border><el-table-column prop="changeTime" label="变更时间" min-width="170"/><el-table-column prop="changeUser" label="变更人" min-width="120"/><el-table-column prop="content" label="变更内容" min-width="360"><template #default="{ row }"><div class="loading-route-change-dialog__record-content">{{ row.content || '-' }}</div></template></el-table-column><el-table-column prop="remark" label="备注" min-width="200" show-overflow-tooltip/></el-table><el-empty v-if="!routeChangeRecords.length" description="暂无变更记录" :image-size="60"/></el-tab-pane>
       </el-tabs>
@@ -2631,6 +2631,9 @@ export default {
     gap: 16px;
     align-items: start;
     //margin-bottom: 12px;
+    .section-card {
+      min-height: 257px;
+    }
   }
 
   .loading-manage-dialog__candidate-actions,