feat: update Cloudflare Stream configuration with sample video ID and customer domain

- Set default videoId and customerDomain in video-demo component for testing purposes
- Enhance demo capabilities by providing a specific Cloudflare Stream configuration

src/views/demo/video-demo.vue

@@ -183,8 +183,8 @@ const urlConfig = reactive({
 
 // Cloudflare Stream 配置
 const cfConfig = reactive({
-  videoId: '',
-  customerDomain: '',
+  videoId: '3c1ae1949e76f200feef94b8f7d093ca',
+  customerDomain: 'customer-pj89kn2ke2tcuh19.cloudflarestream.com',
   playMode: 'iframe' as 'iframe' | 'hls'
 })
 const cfGeneratedUrl = ref('')