fix: configure general rule for trailing slash (npmx-dev#649)

Author: alexdln

app/middleware/trailing-slash.global.ts

@@ -0,0 +1,23 @@
+/**
+ * Removes trailing slashes from URLs.
+ *
+ * This middleware only runs in development to maintain consistent behavior.
+ * In production, Vercel handles this redirect via vercel.json.
+ *
+ * - /package/vue/ → /package/vue
+ * - /docs/getting-started/?query=value → /docs/getting-started?query=value
+ */
+export default defineNuxtRouteMiddleware(to => {
+  if (!import.meta.dev) return
+
+  if (to.path !== '/' && to.path.endsWith('/')) {
+    return navigateTo(
+      {
+        path: to.path.slice(0, -1),
+        query: to.query,
+        hash: to.hash,
+      },
+      { replace: true },
+    )
+  }
+})

vercel.json

@@ -1,5 +1,6 @@
 {
   "$schema": "https://openapi.vercel.sh/vercel.json",
+  "trailingSlash": false,
   "redirects": [
     {
       "source": "/",