feat: improve planning engine travel handling, itinerary reordering, and scenario planners

Add TravelInfo initializers and city normalization helpers to fix repeat
city-pair disambiguation. Improve drag-and-drop reordering with segment
index tracking and source-row-aware zone calculation. Enhance all five
scenario planners with better next-day departure handling and travel
segment placement. Add comprehensive tests across all planners.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

SportsTime/Planning/Engine/ScenarioBPlanner.swift

@@ -75,6 +75,26 @@ final class ScenarioBPlanner: ScenarioPlanner {
             )
         }
 
+        // In explicit date-range mode, fail fast if selected anchors are out of range.
+        let isGameFirstMode = request.preferences.planningMode == .gameFirst
+        if !isGameFirstMode, let explicitRange = request.dateRange {
+            let outOfRangeAnchors = selectedGames.filter { !explicitRange.contains($0.startTime) }
+            if !outOfRangeAnchors.isEmpty {
+                return .failure(
+                    PlanningFailure(
+                        reason: .dateRangeViolation(games: outOfRangeAnchors),
+                        violations: [
+                            ConstraintViolation(
+                                type: .dateRange,
+                                description: "\(outOfRangeAnchors.count) selected game(s) are outside the requested date range",
+                                severity: .error
+                            )
+                        ]
+                    )
+                )
+            }
+        }
+
         // ──────────────────────────────────────────────────────────────────
         // Step 2: Generate date ranges (sliding window or single range)
         // ──────────────────────────────────────────────────────────────────