feat(itinerary): add row views for itinerary items

Add specialized row components for the new unified itinerary system:
- DayHeaderRow: Day number, date display, and add item button
- GameItemRow: Prominent card with sport color bar for games
- TravelItemRow: Gold-styled travel segments with drag handle
- CustomItemRow: Minimal custom items with icon, title, and optional time

All views follow existing Theme patterns and use SportColorBar for consistency.

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

SportsTime/Features/Trip/Views/ItineraryRows/DayHeaderRow.swift

@@ -0,0 +1,54 @@
+//
+//  DayHeaderRow.swift
+//  SportsTime
+//
+//  Header row for a day in the itinerary with day number, date, and add button.
+//
+
+import SwiftUI
+
+struct DayHeaderRow: View {
+    let dayNumber: Int
+    let date: Date
+    let onAddTapped: () -> Void
+
+    @Environment(\.colorScheme) private var colorScheme
+
+    private var formattedDate: String {
+        date.formatted(.dateTime.weekday(.wide).month().day())
+    }
+
+    var body: some View {
+        HStack {
+            VStack(alignment: .leading, spacing: 2) {
+                Text("Day \(dayNumber)")
+                    .font(.title3)
+                    .fontWeight(.semibold)
+                    .foregroundStyle(Theme.textPrimary(colorScheme))
+
+                Text(formattedDate)
+                    .font(.subheadline)
+                    .foregroundStyle(Theme.textSecondary(colorScheme))
+            }
+
+            Spacer()
+
+            Button(action: onAddTapped) {
+                Image(systemName: "plus.circle.fill")
+                    .font(.title2)
+                    .foregroundStyle(Theme.warmOrange)
+            }
+        }
+        .padding(.vertical, Theme.Spacing.sm)
+        .padding(.horizontal, Theme.Spacing.md)
+    }
+}
+
+#Preview {
+    VStack {
+        DayHeaderRow(dayNumber: 1, date: Date(), onAddTapped: {})
+        DayHeaderRow(dayNumber: 2, date: Date().addingTimeInterval(86400), onAddTapped: {})
+    }
+    .padding()
+    .background(Color.gray.opacity(0.1))
+}