added coverage script

Author: MichaelD3289

package.json

@@ -9,7 +9,8 @@
     "build": "tsc && vite build",
     "preview": "vite preview",
     "test": "vitest",
-    "testui": "vitest --ui"
+    "testui": "vitest --ui",
+    "coverage": "vitest run --coverage"
   },
   "dependencies": {
     "react": "^18.2.0",