feat(expenses): combobox trip-label picker (free text + past suggestions)

Replaces the HTML5 datalist Input with a Popover + cmdk Combobox
modeled after CountryCombobox. Free-text on first entry via the
"Create '<typed value>'" item; past labels grouped under "Past trips"
with a check-mark indicating the current selection. Reuses the
existing /api/v1/expenses/trip-labels endpoint (distinct values for
the port, ordered by most-recent expense date) — no new schema or
service work.

Drops useQuery from expense-form-dialog since the combobox now owns
its own data fetch.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/expenses/expense-form-dialog.tsx

@@ -3,7 +3,7 @@
 import { useEffect, useRef, useState } from 'react';
 import { useForm } from 'react-hook-form';
 import { zodResolver } from '@hookform/resolvers/zod';
-import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
+import { useMutation, useQueryClient } from '@tanstack/react-query';
 import { AlertTriangle, Loader2, Upload, X } from 'lucide-react';
 
 import { Button } from '@/components/ui/button';
@@ -21,6 +21,7 @@ import {
 import { Sheet, SheetContent, SheetHeader, SheetTitle, SheetFooter } from '@/components/ui/sheet';
 import { CurrencyInput } from '@/components/shared/currency-input';
 import { CurrencySelect } from '@/components/shared/currency-select';
+import { TripLabelCombobox } from '@/components/expenses/trip-label-combobox';
 import { apiFetch } from '@/lib/api/client';
 import { createExpenseSchema, type CreateExpenseInput } from '@/lib/validators/expenses';
 import { EXPENSE_CATEGORIES, PAYMENT_METHODS } from '@/lib/constants';
@@ -62,16 +63,6 @@ export function ExpenseFormDialog({ open, onOpenChange, expense }: ExpenseFormDi
     },
   });
 
-  // Distinct trip labels for the port — fed into the datalist so the
-  // form input doubles as an autocomplete. Cached for the dialog's life
-  // since the list rarely changes mid-session.
-  const tripLabelsQuery = useQuery<{ data: string[] }>({
-    queryKey: ['expenses', 'trip-labels'],
-    queryFn: () => apiFetch('/api/v1/expenses/trip-labels'),
-    enabled: open,
-    staleTime: 60_000,
-  });
-
   useEffect(() => {
     if (open && expense) {
       reset({
@@ -234,9 +225,7 @@ export function ExpenseFormDialog({ open, onOpenChange, expense }: ExpenseFormDi
               <CurrencySelect
                 id="currency"
                 value={watch('currency') ?? 'USD'}
-                onValueChange={(v) =>
-                  setValue('currency', v, { shouldDirty: true })
-                }
+                onValueChange={(v) => setValue('currency', v, { shouldDirty: true })}
               />
               {errors.currency && (
                 <p className="text-xs text-destructive">{errors.currency.message}</p>
@@ -317,25 +306,14 @@ export function ExpenseFormDialog({ open, onOpenChange, expense }: ExpenseFormDi
 
           <div className="space-y-2">
             <Label htmlFor="tripLabel">Trip / event</Label>
-            <Input
+            <TripLabelCombobox
               id="tripLabel"
+              value={watch('tripLabel') ?? ''}
+              onChange={(label) => setValue('tripLabel', label ?? undefined, { shouldDirty: true })}
               placeholder="e.g. Palm Beach 2026 (optional)"
-              maxLength={120}
-              list="expense-trip-label-suggestions"
-              autoComplete="off"
-              {...register('tripLabel')}
             />
-            {/* Native datalist gives the rep prior trip values as
-             *  autocomplete suggestions — keeps spellings consistent
-             *  ("Palm Beach 2026" vs "palm-beach 2026") so the PDF
-             *  group-by-trip section actually merges them. */}
-            <datalist id="expense-trip-label-suggestions">
-              {(tripLabelsQuery.data?.data ?? []).map((label) => (
-                <option key={label} value={label} />
-              ))}
-            </datalist>
             <p className="text-xs text-muted-foreground">
-              Group expenses by yacht show or business trip. Leave empty for everyday spend.
+              Group expenses by yacht show or business trip. Pick a past trip or type a new one.
             </p>
           </div>
 

src/components/expenses/trip-label-combobox.tsx

@@ -0,0 +1,127 @@
+'use client';
+
+import { useState } from 'react';
+import { useQuery } from '@tanstack/react-query';
+import { Check, ChevronsUpDown, Plus } from 'lucide-react';
+
+import { Button } from '@/components/ui/button';
+import {
+  Command,
+  CommandEmpty,
+  CommandGroup,
+  CommandInput,
+  CommandItem,
+  CommandList,
+} from '@/components/ui/command';
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
+import { apiFetch } from '@/lib/api/client';
+import { cn } from '@/lib/utils';
+
+interface TripLabelComboboxProps {
+  value: string | null | undefined;
+  onChange: (label: string | null) => void;
+  placeholder?: string;
+  disabled?: boolean;
+  id?: string;
+}
+
+/**
+ * Trip label picker. Free-text on first entry, dropdown of past labels
+ * on subsequent ones. The "Create '<typed value>'" item lets reps
+ * commit a brand-new label without leaving the keyboard. Past labels
+ * come from /api/v1/expenses/trip-labels (distinct values for the
+ * port, ordered by most-recent expense date).
+ */
+export function TripLabelCombobox({
+  value,
+  onChange,
+  placeholder = 'Select or create a trip…',
+  disabled,
+  id,
+}: TripLabelComboboxProps) {
+  const [open, setOpen] = useState(false);
+  const [search, setSearch] = useState('');
+
+  const labelsQuery = useQuery<{ data: string[] }>({
+    queryKey: ['expenses', 'trip-labels'],
+    queryFn: () => apiFetch('/api/v1/expenses/trip-labels'),
+    enabled: open,
+    staleTime: 60_000,
+  });
+
+  const labels = labelsQuery.data?.data ?? [];
+  const trimmed = search.trim();
+  const showCreate =
+    trimmed.length > 0 && !labels.some((l) => l.toLowerCase() === trimmed.toLowerCase());
+
+  const commit = (label: string | null) => {
+    onChange(label);
+    setOpen(false);
+    setSearch('');
+  };
+
+  return (
+    <Popover open={open} onOpenChange={setOpen}>
+      <PopoverTrigger asChild>
+        <Button
+          id={id}
+          type="button"
+          variant="outline"
+          role="combobox"
+          aria-expanded={open}
+          disabled={disabled}
+          className={cn('w-full justify-between font-normal', !value && 'text-muted-foreground')}
+        >
+          <span className="truncate">{value || placeholder}</span>
+          <ChevronsUpDown className="ml-2 h-4 w-4 shrink-0 opacity-50" />
+        </Button>
+      </PopoverTrigger>
+      <PopoverContent className="w-[var(--radix-popper-anchor-width)] min-w-[260px] p-0">
+        <Command shouldFilter={true}>
+          <CommandInput
+            placeholder="Type a trip name…"
+            value={search}
+            onValueChange={setSearch}
+            maxLength={120}
+          />
+          <CommandList>
+            <CommandEmpty>
+              {trimmed ? `No matches for "${trimmed}"` : 'No past trips yet'}
+            </CommandEmpty>
+            {value ? (
+              <CommandGroup>
+                <CommandItem
+                  value="__clear__"
+                  onSelect={() => commit(null)}
+                  className="text-muted-foreground"
+                >
+                  Clear selection
+                </CommandItem>
+              </CommandGroup>
+            ) : null}
+            {showCreate ? (
+              <CommandGroup heading="New">
+                <CommandItem value={`__create__${trimmed}`} onSelect={() => commit(trimmed)}>
+                  <Plus className="mr-2 h-4 w-4" />
+                  <span className="truncate">Create &ldquo;{trimmed}&rdquo;</span>
+                </CommandItem>
+              </CommandGroup>
+            ) : null}
+            {labels.length > 0 ? (
+              <CommandGroup heading="Past trips">
+                {labels.map((label) => (
+                  <CommandItem key={label} value={label} onSelect={() => commit(label)}>
+                    <Check
+                      className={cn('mr-2 h-4 w-4', value === label ? 'opacity-100' : 'opacity-0')}
+                    />
+                    <span className="truncate">{label}</span>
+                  </CommandItem>
+                ))}
+              </CommandGroup>
+            ) : null}
+          </CommandList>
+        </Command>
+      </PopoverContent>
+    </Popover>
+  );
+}