feat(trips): trip tracking with analytics, tag conversion, and transaction assignment

Adds trips table usage across API and UI: trip CRUD, per-trip analytics
(category/daily/merchant/tag/participant breakdowns), tag-to-trip
conversion, trip assignment via transaction overrides, and trip filter
in the transactions view. Recovered from working tree after local git
corruption; feature was already live via host-context Docker builds.

src/components/edit-transaction-modal.tsx

@@ -7,6 +7,7 @@ import {
   useAddTransactionTag,
   useRemoveTransactionTag,
   useTransactionSplits,
+  useTrips,
 } from "@/lib/hooks";
 import { SplitModal } from "./split-modal";
 import { CATEGORIES, formatCategory } from "@/lib/categories";
@@ -93,6 +94,7 @@ export function EditTransactionModal({
 }) {
   const isManual = !transaction.statement_id;
   const updateTxn = useUpdateTransaction();
+  const { data: trips = [] } = useTrips();
 
   // Editable override fields
   const [merchant, setMerchant] = useState(transaction.merchant_override ?? transaction.merchant_normalized ?? "");
@@ -105,6 +107,8 @@ export function EditTransactionModal({
   const [description, setDescription] = useState(transaction.description);
   const [amount, setAmount] = useState(String(transaction.amount));
 
+  const [tripId, setTripId] = useState<number | null>(transaction.trip_id ?? null);
+
   // Splits — live via hook so they refresh after SplitModal saves
   const { data: liveSplits = [] } = useTransactionSplits(transaction.id);
 
@@ -136,6 +140,9 @@ export function EditTransactionModal({
           patch.amount = parseFloat(amount);
       }
 
+      if (tripId !== (transaction.trip_id ?? null))
+        patch.trip_id = tripId;
+
       await updateTxn.mutateAsync(patch);
       onClose();
     } catch (e) {
@@ -255,6 +262,21 @@ export function EditTransactionModal({
               </div>
             </div>
 
+            {/* Trip */}
+            <div>
+              <label className="block text-xs text-zinc-500 mb-1">Trip</label>
+              <select
+                value={tripId ?? ""}
+                onChange={(e) => setTripId(e.target.value ? Number(e.target.value) : null)}
+                className="w-full bg-zinc-800 border border-zinc-700 rounded px-2 py-1.5 text-sm"
+              >
+                <option value="">— No Trip —</option>
+                {trips.filter((t) => !t.archived).map((t) => (
+                  <option key={t.id} value={t.id}>{t.name}</option>
+                ))}
+              </select>
+            </div>
+
             {/* Tags */}
             <div>
               <p className="text-xs text-zinc-500 mb-1.5">Tags</p>