Fix static export issues for Next.js 16 App Router

- Updated params to be Promise type (Next.js 15+ breaking change)
- Wrapped useSearchParams() calls in Suspense boundaries for static export
- Fixed signin, signup, and signup-confirm pages
- All 17 routes now build successfully with static export

Build output:
- Static pages: 14 routes
- SSG pages: 3 blog posts (ai-chat, rdbms-analytics, rdbms-jobs)

Author: claude

MyApp.Client/app/signin/page.tsx

@@ -1,7 +1,7 @@
 'use client'
 
 import {serializeToObject} from "@servicestack/client"
-import {SyntheticEvent, useEffect, useState} from "react"
+import {SyntheticEvent, useEffect, useState, Suspense} from "react"
 import {useRouter, useSearchParams} from "next/navigation"
 import Link from "next/link"
 
@@ -11,8 +11,7 @@ import {Authenticate} from "@/lib/dtos"
 import {appAuth, Redirecting} from "@/lib/auth"
 import {getRedirect} from "@/lib/gateway"
 
-export default function SignIn() {
-
+function SignInForm() {
     const client = useClient()
     const [username, setUsername] = useState<string | number>()
     const [password, setPassword] = useState<string | number>()
@@ -91,3 +90,11 @@ export default function SignIn() {
         </div>
     </Page>)
 }
+
+export default function SignIn() {
+    return (
+        <Suspense fallback={<div>Loading...</div>}>
+            <SignInForm />
+        </Suspense>
+    )
+}

MyApp.Client/app/signup-confirm/page.tsx

@@ -1,9 +1,10 @@
 'use client'
 
+import { Suspense } from "react"
 import Page from "@/components/layout-page"
 import { useSearchParams } from "next/navigation"
 
-export default function SignUpConfirm() {
+function SignUpConfirmContent() {
     const searchParams = useSearchParams()
     const confirmLink = searchParams.get('confirmLink')
 
@@ -20,3 +21,11 @@ export default function SignUpConfirm() {
         </div>
     </Page>)
 }
+
+export default function SignUpConfirm() {
+    return (
+        <Suspense fallback={<div>Loading...</div>}>
+            <SignUpConfirmContent />
+        </Suspense>
+    )
+}

MyApp.Client/app/signup/page.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import { SyntheticEvent, useEffect, useState } from "react"
+import { SyntheticEvent, useEffect, useState, Suspense } from "react"
 import { useClient, FormLoading, ErrorSummary, TextInput, PrimaryButton, SecondaryButton, ApiStateContext } from "@servicestack/react"
 import { serializeToObject, leftPart, rightPart, toPascalCase } from "@servicestack/client"
 import {useRouter, useSearchParams} from "next/navigation"
@@ -9,8 +9,7 @@ import { getRedirect } from "@/lib/gateway"
 import { Register, RegisterResponse } from "@/lib/dtos"
 import { appAuth, Redirecting } from "@/lib/auth"
 
-export default function SignUp() {
-
+function SignUpForm() {
     const client = useClient()
     const [displayName, setDisplayName] = useState<string>()
     const [username, setUsername] = useState<string>()
@@ -100,3 +99,11 @@ export default function SignUp() {
         </div>
     </Page>)
 }
+
+export default function SignUp() {
+    return (
+        <Suspense fallback={<div>Loading...</div>}>
+            <SignUpForm />
+        </Suspense>
+    )
+}