refactor: 更新搜索页面样式和逻辑以支持多端兼容性

- 修改 search.scss 文件，优化样式以适应小程序和 H5/APP-PLUS 端
- 更新 searchPage.vue 文件，调整条件编译指令以支持多端展示
- 移除不必要的计算逻辑，简化代码结构，提高可读性

pages/navigation/search/search.scss

@@ -133,14 +133,23 @@ page {
     margin-bottom: 20rpx;
   }
 }
-.scoll-page,
-.goods-scroll {
+.scoll-page {
   flex: 1;
   min-height: 0;
   height: 100%;
   box-sizing: border-box;
 }
 
+/* #ifdef MP */
+.goods-scroll {
+  flex: 1;
+  height: 0;
+  min-height: 0;
+  width: 100%;
+  box-sizing: border-box;
+}
+/* #endif */
+
 .search-navbar-wrap {
   box-sizing: border-box;
   flex-shrink: 0;
@@ -163,6 +172,12 @@ page {
   background: $bg-color;
 }
 
+/* #ifdef MP */
+.goods-content {
+  height: 0;
+}
+/* #endif */
+
 .content {
   background-color: $bg-color;
   height: 100vh;
@@ -171,14 +186,16 @@ page {
   flex-direction: column;
 }
 
-/* #ifdef H5 */
+/* #ifdef H5 || APP-PLUS */
 .content--goods {
+  display: block;
   height: auto;
   min-height: 100vh;
   overflow: visible;
 }
 
 .goods-content--h5 {
+  display: block;
   flex: none;
   min-height: auto;
   overflow: visible;
@@ -440,6 +457,7 @@ page {
   display: flex;
   width: 100%;
   height: 80rpx;
+  flex-shrink: 0;
   background: #fff;
   box-shadow: 0 2rpx 10rpx rgba(0, 0, 0, 0.06);
   z-index: 10;