Add EV charging discovery feature (disabled by flag)

- Create EVChargingService using MapKit POI search for EV chargers
- Add ItineraryBuilder.enrichWithEVChargers() for post-planning enrichment
- Update TravelSection in TripDetailView with expandable charger list
- Add FeatureFlags.enableEVCharging toggle (default: false)
- Include EVChargingFeature.md documenting API overhead

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

SportsTime/Features/Trip/ViewModels/TripCreationViewModel.swift

@@ -313,11 +313,19 @@ final class TripCreationViewModel {
             let result = planningEngine.planItineraries(request: request)
 
             switch result {
-            case .success(let options):
+            case .success(var options):
                 guard !options.isEmpty else {
                     viewState = .error("No valid itinerary found")
                     return
                 }
+
+                // Enrich with EV chargers if requested and feature is enabled
+                if FeatureFlags.enableEVCharging && needsEVCharging {
+                    print("[TripCreation] Enriching \(options.count) options with EV chargers...")
+                    options = await ItineraryBuilder.enrichWithEVChargers(options)
+                    print("[TripCreation] EV charger enrichment complete")
+                }
+
                 // Store preferences for later conversion
                 currentPreferences = preferences