fix: viewport metadata (Next.js 15), lazy auth client init (location SSR error), force-dynamic dashboard

lib/auth-client.ts

@@ -2,8 +2,18 @@
 
 import { createAuthClient } from "better-auth/react"
 
-export const authClient = createAuthClient({
-  baseURL: process.env.NEXT_PUBLIC_APP_URL || "http://localhost:3000",
-})
+let client: ReturnType<typeof createAuthClient> | null = null
 
-export const { signIn, signUp, useSession } = authClient
+function initClient() {
+  if (typeof window === "undefined") return
+  if (!client) {
+    client = createAuthClient({
+      baseURL: process.env.NEXT_PUBLIC_APP_URL || "http://localhost:3000",
+    })
+  }
+  return client
+}
+
+export function getAuth() {
+  return initClient()
+}