feat(remix): support serving app under a sub-path via NEXT_PUBLIC_BASE_PATH (#2824)

apps/remix/react-router.config.ts

@@ -3,4 +3,9 @@ import type { Config } from '@react-router/dev/config';
 export default {
   appDirectory: 'app',
   ssr: true,
+  // Must never be undefined and must start with the raw Vite `base` value,
+  // otherwise @react-router/dev crashes / exits on `react-router dev`. Both are
+  // kept without a trailing slash so they match exactly, and so the bare
+  // sub-path URL (e.g. "/ESign") still matches the basename at runtime.
+  basename: process.env.NEXT_PUBLIC_BASE_PATH ? process.env.NEXT_PUBLIC_BASE_PATH.replace(/\/$/, '') : '/',
 } satisfies Config;