fix(itinerary): add city to game items for proper constraint validation

Travel constraint validation was not working because ItineraryConstraints
had no game items to validate against - games came from RichGame objects
but were never converted to ItineraryItem for constraint checking.

Changes:
- Add city parameter to ItemKind.game enum case
- Create game ItineraryItems from RichGame data in buildItineraryData()
- Update isValidTravelPosition to compare against actual game sortOrders
- Fix tests to use appropriate game sortOrder conventions

Now travel is properly constrained to appear before arrival city games
and after departure city games.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

SportsTime/Features/Trip/Views/TripDetailView.swift

@@ -203,7 +203,7 @@ struct TripDetailView: View {
                         withAnimation {
                             travelOverrides[travelId] = TravelOverride(day: newDay, sortOrder: newSortOrder)
                         }
-                        await saveTravelDayOverride(travelAnchorId: travelId, displayDay: newDay)
+                        await saveTravelDayOverride(travelAnchorId: travelId, displayDay: newDay, sortOrder: newSortOrder)
                     }
                 },
                 onCustomItemMoved: { itemId, day, sortOrder in
@@ -1371,7 +1371,8 @@ struct TripDetailView: View {
                         // Persist to CloudKit as a travel ItineraryItem
                         await self.saveTravelDayOverride(
                             travelAnchorId: droppedId,
-                            displayDay: dayNumber
+                            displayDay: dayNumber,
+                            sortOrder: newSortOrder
                         )
                         return
                     }
@@ -1393,8 +1394,8 @@ struct TripDetailView: View {
         return false
     }
 
-    private func saveTravelDayOverride(travelAnchorId: String, displayDay: Int) async {
-        print("💾 [TravelOverrides] Saving override: \(travelAnchorId) -> day \(displayDay)")
+    private func saveTravelDayOverride(travelAnchorId: String, displayDay: Int, sortOrder: Double) async {
+        print("💾 [TravelOverrides] Saving override: \(travelAnchorId) -> day \(displayDay), sortOrder \(sortOrder)")
 
         // Parse travel ID to extract cities (format: "travel:city1->city2")
         let stripped = travelAnchorId.replacingOccurrences(of: "travel:", with: "")
@@ -1414,6 +1415,7 @@ struct TripDetailView: View {
             // Update existing
             var updated = itineraryItems[existingIndex]
             updated.day = displayDay
+            updated.sortOrder = sortOrder
             updated.modifiedAt = Date()
             itineraryItems[existingIndex] = updated
             await ItineraryItemService.shared.updateItem(updated)
@@ -1423,7 +1425,7 @@ struct TripDetailView: View {
             let item = ItineraryItem(
                 tripId: trip.id,
                 day: displayDay,
-                sortOrder: 0,  // Travel always comes first in day
+                sortOrder: sortOrder,
                 kind: .travel(travelInfo)
             )
             itineraryItems.append(item)