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/Core/Services/ItineraryItemService.swift

@@ -145,8 +145,9 @@ extension ItineraryItem {
         // Parse kind
         switch kindString {
         case "game":
-            guard let gameId = record["gameId"] as? String else { return nil }
-            self.kind = .game(gameId: gameId)
+            guard let gameId = record["gameId"] as? String,
+                  let gameCity = record["gameCity"] as? String else { return nil }
+            self.kind = .game(gameId: gameId, city: gameCity)
 
         case "travel":
             guard let fromCity = record["travelFromCity"] as? String,
@@ -188,9 +189,10 @@ extension ItineraryItem {
         record["modifiedAt"] = modifiedAt
 
         switch kind {
-        case .game(let gameId):
+        case .game(let gameId, let city):
             record["kind"] = "game"
             record["gameId"] = gameId
+            record["gameCity"] = city
 
         case .travel(let info):
             record["kind"] = "travel"