feat: customer lookup from POS with order history and item search

- Customer dialog in cart panel: search accounts by name, phone, email, account #
- Selected customer shown with name, phone, email in cart header
- accountId passed when creating transactions
- Order history view: tap a transaction to expand and see line items
- Item search in history (e.g. "strings") — filters orders containing that item
- Backend: add accountId and itemSearch filters to transaction list endpoint
- itemSearch uses EXISTS subquery on line item descriptions (ILIKE)

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

packages/admin/src/components/pos/pos-cart-panel.tsx

@@ -3,10 +3,11 @@ import { usePOSStore } from '@/stores/pos.store'
 import { posMutations, posKeys, type Transaction } from '@/api/pos'
 import { Button } from '@/components/ui/button'
 import { Separator } from '@/components/ui/separator'
-import { X, Banknote, CreditCard, FileText, Ban } from 'lucide-react'
+import { X, Banknote, CreditCard, FileText, Ban, UserRound } from 'lucide-react'
 import { toast } from 'sonner'
 import { useState } from 'react'
 import { POSPaymentDialog } from './pos-payment-dialog'
+import { POSCustomerDialog } from './pos-customer-dialog'
 
 interface POSCartPanelProps {
   transaction: Transaction | null
@@ -14,8 +15,9 @@ interface POSCartPanelProps {
 
 export function POSCartPanel({ transaction }: POSCartPanelProps) {
   const queryClient = useQueryClient()
-  const { currentTransactionId, setTransaction } = usePOSStore()
+  const { currentTransactionId, setTransaction, accountName, accountPhone, accountEmail } = usePOSStore()
   const [paymentMethod, setPaymentMethod] = useState<string | null>(null)
+  const [customerOpen, setCustomerOpen] = useState(false)
   const lineItems = transaction?.lineItems ?? []
 
   const drawerSessionId = usePOSStore((s) => s.drawerSessionId)
@@ -63,6 +65,24 @@ export function POSCartPanel({ transaction }: POSCartPanelProps) {
             </span>
           )}
         </div>
+        <button
+          onClick={() => setCustomerOpen(true)}
+          className="flex items-start gap-1.5 mt-1 text-xs text-muted-foreground hover:text-foreground text-left"
+        >
+          <UserRound className="h-3 w-3 mt-0.5 shrink-0" />
+          {accountName ? (
+            <span>
+              <span className="font-medium text-foreground">{accountName}</span>
+              {(accountPhone || accountEmail) && (
+                <span className="block text-[11px]">
+                  {[accountPhone, accountEmail].filter(Boolean).join(' · ')}
+                </span>
+              )}
+            </span>
+          ) : (
+            <span>Walk-in — tap to add customer</span>
+          )}
+        </button>
       </div>
 
       {/* Line items */}
@@ -182,6 +202,9 @@ export function POSCartPanel({ transaction }: POSCartPanelProps) {
           onComplete={handlePaymentComplete}
         />
       )}
+
+      {/* Customer dialog */}
+      <POSCustomerDialog open={customerOpen} onOpenChange={setCustomerOpen} />
     </div>
   )
 }