Allow deployed frontend host

frontend/vite.config.ts

@@ -1,10 +1,19 @@
-import { defineConfig } from "vite";
+import { defineConfig, loadEnv } from "vite";
 import react from "@vitejs/plugin-react-swc";
 
-export default defineConfig({
-  plugins: [react()],
-  server: {
-    host: "0.0.0.0",
-    port: 5173,
-  },
+export default defineConfig(({ mode }) => {
+  const env = loadEnv(mode, process.cwd(), "");
+  const allowedHosts = (env.VITE_ALLOWED_HOSTS ?? "localhost,127.0.0.1,plasttrack.sable.ynsdev.site")
+    .split(",")
+    .map((host) => host.trim())
+    .filter(Boolean);
+
+  return {
+    plugins: [react()],
+    server: {
+      host: "0.0.0.0",
+      port: 5173,
+      allowedHosts,
+    },
+  };
 });