refactor(merchcategory): add bottom tabbar and optimize page layout

1. add diy bottom navigation component to the merch category page
2. replace hardcoded height style with dynamic computed style based on tabbar status
3. add unified page path mapping and url resolution utilities
4. update page jump logic to use new page_key based routing

pages_promotion/merch/merchcategory.vue

@@ -1,6 +1,6 @@
 <template>
 	<view :style="themeColor">
-		<view class="category-page-wrap category-template-1" style="height: calc(-56px + 100vh);">
+		<view class="category-page-wrap category-template-1" :style="categoryPageStyle">
 
 		<!-- 	<view class="search-box" @click="$util.redirectTo('/pages_tool/goods/search')">
 				<view class="search-content">
@@ -56,6 +56,11 @@
 		<ns-login ref="login"></ns-login>
 	<!-- 	<loading-cover ref="loadingCover"></loading-cover> -->
 
+		<!-- 底部tabBar -->
+		<view class="page-bottom">
+			<diy-bottom-nav></diy-bottom-nav>
+		</view>
+
 	</view>
 </template>
 
@@ -85,9 +90,18 @@
 						]
 					},*/
 					
-			],
-			user_type:uni.getStorageSync('user_type')
-		};
+				],
+				user_type:uni.getStorageSync('user_type')
+			};
+		},
+		computed: {
+			categoryPageStyle() {
+				const hasTabBar = this.tabBarList && this.tabBarList.list;
+				return this.$util.objToStyle({
+					height: 'calc(100vh - 56px)',
+					paddingBottom: hasTabBar ? '112rpx' : '0'
+				});
+			}
 		},
 		onLoad() {
 			uni.hideTabBar()