style(theme): 统一应用主题样式并更新组件样式变量

- 在多个页面组件中添加动态主题样式绑定
- 将硬编码的颜色值替换为CSS变量和主题配置
- 引入主题样式计算逻辑到各个页面
- 更新优惠券、地址、订单等页面的主题适配
- 替换线性渐变背景为动态主题颜色
- 移除uni_modules组件中的$set方法调用以优化性能
- 更新README中主题色管理状态为已完成

pages/promotion/bargain/list.vue

@@ -1,5 +1,5 @@
 <template>
-  <div class="page">
+  <div :style="themeStyle" class="page">
     <u-navbar :auto-back="false" @leftClick="back" left-icon-color="#fff" :bg-color="background.backgroundColor" :border="false" >
     </u-navbar>
     <div class="wrapper">
@@ -16,10 +16,14 @@
 </template>
 
 <script setup lang="ts">
-import { ref } from 'vue'
+import { ref, computed } from 'vue'
 import { onShow, onReachBottom } from '@dcloudio/uni-app'
 import { getBargainList } from '@/api/promotions'
 import goodsTemplate from '@/components/m-goods-list/promotion'
+import { useStore } from '@/store'
+import { getThemeStyle } from '@/utils/theme'
+const store = useStore()
+const themeStyle = computed(() => getThemeStyle(store.state.theme))
 
 const background = ref({
   backgroundColor: 'transparent',