业务更名为撞车并切换crash路由

用户可见文案与页面/API路径改为撞车与crash，保留mohong表与权限码兼容；移动端入口去掉租/撞图标。

frontend/src/features/mohong/views/MohongDetailView.vue

@@ -146,11 +146,11 @@ async function handleBuy() {
     const payment = await startMohongPayment(order.id, payWay)
     if (payment.paid || payment.status === 'paid') {
       ElMessage.success('支付成功')
-      await router.push(`/mohong/orders/${order.id}`)
+      await router.push(`/crash/orders/${order.id}`)
       return
     }
     await cashier.openPaymentCashier(payment, async () => {
-      await router.push(`/mohong/orders/${order.id}`)
+      await router.push(`/crash/orders/${order.id}`)
     })
   } catch (error) {
     ElMessage.error(readError(error, '下单失败'))
@@ -184,7 +184,7 @@ async function handleBuy() {
         </div>
 
         <div class="info-panel">
-          <p class="eyebrow">摸大红商品</p>
+          <p class="eyebrow">撞车商品</p>
           <h1>{{ product.title }}</h1>
           <p class="desc">{{ product.description || '暂无说明' }}</p>
 
@@ -238,7 +238,7 @@ async function handleBuy() {
             <el-button size="large" class="btn-outline" @click="openCart">
               购物车{{ cartCount > 0 ? `(${cartCount})` : '' }}
             </el-button>
-            <el-button size="large" class="btn-outline" @click="router.push('/mohong')">
+            <el-button size="large" class="btn-outline" @click="router.push('/crash')">
               返回列表
             </el-button>
           </div>