refactor: remove margin utils, use inline pixel spacing

Delete the src/static/scss/margin.scss utility file, update all component templates to replace pre-defined margin classes with inline arbitrary pixel values (e.g. mb-[4px] instead of mb-4), and clean up long template lines for better readability.

src/pages-order/order/components/OrderCard/index.vue

@@ -1,9 +1,9 @@
 <template>
-  <view class="order-card bg-white p-[12px] rounded-[12px] m-12" @click.stop="handleCardClick">
+  <view class="order-card bg-white p-[12px] rounded-[12px] m-[12px]" @click.stop="handleCardClick">
     <!-- 卡片头部 -->
     <view class="card-header flex items-center">
       <view class="status-info flex items-center flex-full">
-        <image class="status-icon mr-4" :src="getStatusIcon()" />
+        <image class="status-icon mr-[4px]" :src="getStatusIcon()" />
         <view class="order-title font-size-14 leading-[20px] text-[#525866]">
           {{ getOrderTypeName() }}
         </view>