refactor: clean up codebase and add new features

Replace SCSS variable usages with explicit pixel/hex values for consistent styling across all components
Fix broken template syntax including missing class spaces and incorrect closing tags
Migrate constant and API imports to centralized @/constants and @/api modules
Add new utility classes: IdUtils, CallbackUtils, and TimerUtils
Add new chat conversation API endpoints for recent conversations and message lists
Add new Discovery page components (FindTabs, QuickQuestions, CardSwiper) and their styles
Update app store config to use environment variables for base API and WebSocket URLs
Add new selected tab icon assets

src/components/RefundPopup/index.vue

@@ -1,27 +1,12 @@
 <template>
-  <uni-popup
-    ref="popupRef"
-    type="bottom"
-    :safe-area="false"
-    @maskClick="handleClose"
-  >
+  <uni-popup ref="popupRef" type="bottom" :safe-area="false" @maskClick="handleClose">
     <div class="refund-popup bg-F5F7FA border-box">
-      <div
-        class="border-box flex flex-items-center justify-between pt-12 pb-12 relative"
-      >
-        <div
-          class="flex-full font-size-16 color-171717 line-height-24 text-center"
-        >
+      <div class="border-box flex flex-items-center justify-between pt-12 pb-12 relative">
+        <div class="flex-full font-size-16 color-171717 line-height-24 text-center">
           取消政策
         </div>
         <!-- 关闭按钮 -->
-        <uni-icons
-          class="close absolute"
-          type="close"
-          size="20"
-          color="#CACFD8"
-          @click="handleClose"
-        />
+        <uni-icons class="close absolute" type="close" size="20" color="#CACFD8" @click="handleClose" />
       </div>
       <!-- 内容区域 -->
       <div class="border-box rounded-12 bg-white p-12 ml-12 mr-12 mb-40">
@@ -29,15 +14,12 @@
           <uni-icons fontFamily="znicons" size="20" color="#333">
             {{ zniconsMap["zn-refund"] }}
           </uni-icons>
-          <spanclass="font-size-14 font-600 color-171717 ml-8">
+          <span class="font-size-14 font-600 color-171717 ml-8">
             {{ refundTitle }}
-          </text>
+          </span>
         </div>
-        <div
-          class="font-size-14 color-525866 line-height-16 mb-4"
-          v-for="(item, index) in commodityPurchaseInstruction"
-          :key="index"
-        >
+        <div class="font-size-14 color-525866 line-height-16 mb-4" v-for="(item, index) in commodityPurchaseInstruction"
+          :key="index">
           {{ item }}
         </div>
       </div>
@@ -59,7 +41,7 @@ const props = defineProps({
   // 订单数据
   orderData: {
     type: Object,
-    default: () => {},
+    default: () => { },
   },
 });