add compile time defines

pairent_frontend_react/vite.config.js

@@ -1,8 +1,13 @@
 import react from '@vitejs/plugin-react'
+import * as child from 'child_process';
 
 /** @type {import('vite').UserConfig} */
 export default {
     plugins: [
         react()
-    ],    
+    ],
+    define: {
+        BUILD_TIME: new Date(),
+        // LAST_COMMIT: JSON.stringify(child.execSync("git rev-parse --short HEAD"))
+    }
 }