feat(ui): 更新任务流程卡片样式和图标

- 引入 Element Plus 图标组件替代原有文字图标
- 移除卡片阴影属性优化视觉效果
- 调整结果区域按钮组布局对齐方式
- 更新文本域样式增加颜色变量支持
- 注释掉编辑卡片背景色定义
- 添加图标依赖包到项目配置

frontend/src/layout/components/Main/TaskTemplate/TaskProcess/ProcessCard.vue

@@ -1,6 +1,7 @@
 <script setup lang="ts">
-import { ref, computed } from 'vue'
+import { ref } from 'vue'
 import { getActionTypeDisplay } from '@/layout/components/config.ts'
+import { CloseBold, Select } from '@element-plus/icons-vue'
 
 const props = defineProps<{
   step: {
@@ -117,20 +118,18 @@ function handleCancel() {
                 <el-button
                   type="success"
                   size="small"
-                  icon="Check"
+                  :icon="Select"
                   @click="handleSave(process.ID)"
                   title="保存"
                 >
-                  √
                 </el-button>
                 <el-button
                   type="danger"
                   size="small"
-                  icon="Close"
+                  :icon="CloseBold"
                   @click="handleCancel"
                   title="取消"
                 >
-                  ×
                 </el-button>
               </div>
             </div>
@@ -196,7 +195,7 @@ function handleCancel() {
 
           .edit-card {
             position: relative;
-            background: #f0f2f5;
+            //background: #f0f2f5;
             border-radius: 8px;
             padding: 16px;
             box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
@@ -213,6 +212,7 @@ function handleCancel() {
                 border-radius: 4px;
                 resize: vertical;
                 min-height: 60px;
+                color: var(--color-text-taskbar);
               }
             }