test: add package.json for issue #1

package.json

@@ -0,0 +1,6 @@
+{
+  "name": "hwacheon-network-viewer-validation",
+  "private": true,
+  "scripts": { "test:ui": "node tests/viewer.cjs" },
+  "devDependencies": { "playwright": "1.62.1" }
+}