add a constant file to read the env variables

ui/lib/constants.ts

@@ -0,0 +1,20 @@
+export const ENV = {
+  WS_URL: process.env.NEXT_PUBLIC_WS_URL,
+  API_URL: process.env.NEXT_PUBLIC_API_URL,
+} as const;
+
+export type ENV = typeof ENV;
+
+// Type guard function
+export function assertEnvVariables(ENV: ENV): asserts ENV is Required<ENV> {
+  const missingVariables = Object.entries(ENV).filter(([_, value]) => value === undefined);
+  if (missingVariables.length > 0) {
+    throw new Error(`Missing environment variables: ${missingVariables.map(([key]) => key).join(", ")}`);
+  }
+}
+
+// Call this function early in your app's initialization
+assertEnvVariables(ENV);
+
+// After assertion, we can safely use ENV
+export const VALIDATED_ENV: Required<ENV> = ENV as Required<ENV>;