fix: production crash due to undefined import.meta.env by adding env utility and updating build script

src/utils/env.ts

@@ -0,0 +1,23 @@
+/**
+ * Safely access environment variables across different runtimes and builders.
+ * Supports Vite's import.meta.env and Bun's process.env (used in bun build).
+ */
+export const getEnv = (key: string, defaultValue = ""): string => {
+	// 1. Try Vite's import.meta.env
+	try {
+		if (typeof import.meta.env !== "undefined" && import.meta.env[key]) {
+			return import.meta.env[key];
+		}
+	} catch {}
+
+	// 2. Try process.env (injected by bun build --env)
+	try {
+		if (typeof process !== "undefined" && process.env[key]) {
+			return process.env[key];
+		}
+	} catch {}
+
+	return defaultValue;
+};
+
+export const VITE_PUBLIC_URL = getEnv("VITE_PUBLIC_URL", "http://localhost:3000");