fix: 场馆与折扣页返回按钮回首页

- 直接链接进入（无历史栈）时返回首页兜底

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

pages/discount/discount.vue

@@ -104,7 +104,13 @@ export default {
 			}
 		},
 		goBack() {
-			uni.navigateBack()
+			// xuchao: 直接通过链接进入（无历史栈）时回到首页
+			const pages = getCurrentPages()
+			if (pages.length > 1) {
+				uni.navigateBack()
+			} else {
+				uni.reLaunch({ url: '/pages/index/index' })
+			}
 		},
 		goDetail(item) {
 			uni.navigateTo({ url: '/pages/venue/detail?id=' + item.shopId })

pages/venue/venue.vue

@@ -104,7 +104,13 @@ export default {
 			}
 		},
 		goBack() {
-			uni.navigateBack()
+			// xuchao: 直接通过链接进入（无历史栈）时回到首页
+			const pages = getCurrentPages()
+			if (pages.length > 1) {
+				uni.navigateBack()
+			} else {
+				uni.reLaunch({ url: '/pages/index/index' })
+			}
 		},
 		goDetail(item) {
 			uni.navigateTo({ url: '/pages/venue/detail?id=' + item.shopId })