feat: forced PIN setup modal on all authenticated pages

Replaces the alert banner with a blocking modal dialog that requires
users to set a PIN before they can use the app. Cannot be dismissed.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/admin/src/routes/_authenticated.tsx

@@ -1,5 +1,5 @@
 import { createFileRoute, Outlet, Link, redirect, useRouter } from '@tanstack/react-router'
-import { useQuery } from '@tanstack/react-query'
+import { useQuery, useQueryClient, useMutation } from '@tanstack/react-query'
 import { queryOptions } from '@tanstack/react-query'
 import { useEffect, useState } from 'react'
 import { api } from '@/lib/api-client'
@@ -8,8 +8,10 @@ import { myPermissionsOptions } from '@/api/rbac'
 import { moduleListOptions } from '@/api/modules'
 import { Avatar } from '@/components/shared/avatar-upload'
 import { Button } from '@/components/ui/button'
-import { Users, UserRound, HelpCircle, Shield, UserCog, LogOut, User, Wrench, Package, ClipboardList, FolderOpen, KeyRound, Settings, PanelLeftClose, PanelLeft, CalendarDays, GraduationCap, CalendarRange, BookOpen, BookMarked, Package2, Tag, Truck, ShoppingCart, AlertTriangle } from 'lucide-react'
+import { Users, UserRound, HelpCircle, Shield, UserCog, LogOut, User, Wrench, Package, ClipboardList, FolderOpen, KeyRound, Settings, PanelLeftClose, PanelLeft, CalendarDays, GraduationCap, CalendarRange, BookOpen, BookMarked, Package2, Tag, Truck, ShoppingCart } from 'lucide-react'
-import { Alert, AlertTitle, AlertDescription } from '@/components/ui/alert'
+import { Input } from '@/components/ui/input'
+import { Label } from '@/components/ui/label'
+import { toast } from 'sonner'
 
 export const Route = createFileRoute('/_authenticated')({
   beforeLoad: () => {
@@ -105,6 +107,58 @@ function NavGroup({ label, children, collapsed }: { label: string; children: Rea
   )
 }
 
+function SetPinModal() {
+  const queryClient = useQueryClient()
+  const [pin, setPin] = useState('')
+  const [confirmPin, setConfirmPin] = useState('')
+  const [error, setError] = useState('')
+
+  const setPinMutation = useMutation({
+    mutationFn: () => api.post('/v1/auth/set-pin', { pin }),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['auth', 'me'] })
+      toast.success('PIN set successfully')
+    },
+    onError: (err) => setError(err.message),
+  })
+
+  function handleSubmit(e: React.FormEvent) {
+    e.preventDefault()
+    setError('')
+    if (pin.length < 4 || pin.length > 6) { setError('PIN must be 4-6 digits'); return }
+    if (!/^\d+$/.test(pin)) { setError('PIN must be digits only'); return }
+    if (pin !== confirmPin) { setError('PINs do not match'); return }
+    setPinMutation.mutate()
+  }
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/60">
+      <div className="w-full max-w-sm rounded-xl border bg-card p-6 shadow-xl">
+        <h2 className="text-lg font-semibold mb-1">Set your POS PIN</h2>
+        <p className="text-sm text-muted-foreground mb-4">
+          A PIN is required to use the Point of Sale. Choose a 4-6 digit PIN you'll use to unlock the terminal.
+        </p>
+        <form onSubmit={handleSubmit} className="space-y-4">
+          <div className="grid grid-cols-2 gap-4">
+            <div className="space-y-2">
+              <Label>PIN</Label>
+              <Input type="password" inputMode="numeric" maxLength={6} value={pin} onChange={(e) => setPin(e.target.value)} placeholder="****" autoFocus />
+            </div>
+            <div className="space-y-2">
+              <Label>Confirm PIN</Label>
+              <Input type="password" inputMode="numeric" maxLength={6} value={confirmPin} onChange={(e) => setConfirmPin(e.target.value)} placeholder="****" />
+            </div>
+          </div>
+          {error && <p className="text-sm text-destructive">{error}</p>}
+          <Button type="submit" className="w-full" disabled={setPinMutation.isPending}>
+            {setPinMutation.isPending ? 'Setting...' : 'Set PIN'}
+          </Button>
+        </form>
+      </div>
+    </div>
+  )
+}
+
 function AuthenticatedLayout() {
   const router = useRouter()
   const user = useAuthStore((s) => s.user)
@@ -271,18 +325,7 @@ function AuthenticatedLayout() {
           </div>
         </nav>
         <main className="flex-1 p-6 min-h-screen">
-          {profile && !profile.hasPin && (
+          {profile && !profile.hasPin && <SetPinModal />}
-            <Alert className="mb-4">
-              <AlertTriangle className="h-4 w-4" />
-              <AlertTitle>POS PIN not set</AlertTitle>
-              <AlertDescription>
-                You need a PIN to use the Point of Sale.{' '}
-                <Link to="/profile" search={{ tab: 'security' }} className="underline font-medium text-foreground">
-                  Set your PIN
-                </Link>
-              </AlertDescription>
-            </Alert>
-          )}
           <Outlet />
         </main>
       </div>