fix(api): correct Next.js App Router handler signatures for key-backup and backup-pin

GET/POST/PUT handlers were receiving `{ request }` (destructuring the
Request object, giving undefined) instead of `request` directly. This
caused every auth check to throw, fall into the catch block, and return
401 Unauthorized — breaking server key backup save, restore, and the
backup-exists check on the settings page.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: ralyodio

src/app/api/auth/backup-pin/route.js

@@ -100,7 +100,7 @@ async function hashPin(pin) {
  * GET /api/auth/backup-pin
  * Check if the authenticated user has a backup PIN set
  */
-export async function GET({ request }) {
+export async function GET(request) {
 	try {
 		const { user, error: authError } = await authenticateUser(request);
 		if (authError || !user) {
@@ -129,7 +129,7 @@ export async function GET({ request }) {
  * POST /api/auth/backup-pin
  * Set or update the backup PIN for the authenticated user
  */
-export async function POST({ request }) {
+export async function POST(request) {
 	try {
 		const { user, error: authError } = await authenticateUser(request);
 		if (authError || !user) {

src/app/api/auth/key-backup/route.js

@@ -91,7 +91,7 @@ async function authenticateUser(request) {
  * GET /api/auth/key-backup
  * Fetch the authenticated user's encrypted key backup
  */
-export async function GET({ request }) {
+export async function GET(request) {
 	try {
 		const { user, error: authError } = await authenticateUser(request);
 		if (authError || !user) {
@@ -131,7 +131,7 @@ export async function GET({ request }) {
  * PUT /api/auth/key-backup
  * Store or update the authenticated user's encrypted key backup
  */
-export async function PUT({ request }) {
+export async function PUT(request) {
 	try {
 		const { user, error: authError } = await authenticateUser(request);
 		if (authError || !user) {