redesign PaywallView with premium header, feature grid, and ticket separator

Replace the generic paywall header with a branded "SportsTime Pro / Your All-Access Pass"
hero section, 4 uniform feature cards (GeometryReader-sized squares), and a dashed ticket
perforation separator. Add "Show Paywall" debug button in Settings.

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

SportsTime/Features/Settings/Views/SettingsView.swift

@@ -543,6 +543,12 @@ struct SettingsView: View {
                 Label("Show Onboarding Flow", systemImage: "play.circle")
             }
 
+            Button {
+                showPaywall = true
+            } label: {
+                Label("Show Paywall", systemImage: "creditcard.fill")
+            }
+
             Button {
                 UserDefaults.standard.removeObject(forKey: "hasSeenOnboardingPaywall")
             } label: {