feat: enforce custom Theme colors app-wide, add debug sample trips and poll

Replace all system colors (.secondary, Color(.secondarySystemBackground),
etc.) with Theme.textPrimary/textSecondary/textMuted/cardBackground/
surfaceGlow across 13 views. Remove PostHog debug logging. Add debug
settings for sample trips and hardcoded group poll preview.

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

SportsTime/Features/Home/Views/HomeView.swift

@@ -450,6 +450,9 @@ struct SavedTripsListView: View {
     @State private var hasLoadedPolls = false
     @State private var showCreatePoll = false
     @State private var selectedPoll: TripPoll?
+    #if DEBUG
+    @State private var showDebugPoll = false
+    #endif
 
     /// Trips sorted by most cities (stops) first
     private var sortedTrips: [SavedTrip] {
@@ -489,6 +492,13 @@ struct SavedTripsListView: View {
         .navigationDestination(for: TripPoll.self) { poll in
             PollDetailView(pollId: poll.id)
         }
+        #if DEBUG
+        .sheet(isPresented: $showDebugPoll) {
+            NavigationStack {
+                DebugPollPreviewView()
+            }
+        }
+        #endif
     }
 
     // MARK: - Polls Section
@@ -519,7 +529,17 @@ struct SavedTripsListView: View {
                     .frame(maxWidth: .infinity, alignment: .center)
                     .padding()
             } else if polls.isEmpty {
+                #if DEBUG
+                // Debug sample poll
+                Button {
+                    showDebugPoll = true
+                } label: {
+                    PollRowCard(poll: DebugShareExporter.buildSamplePoll())
+                }
+                .buttonStyle(.plain)
+                #else
                 emptyPollsCard
+                #endif
             } else {
                 ForEach(polls) { poll in
                     NavigationLink(value: poll) {
@@ -578,15 +598,16 @@ struct SavedTripsListView: View {
                 VStack(spacing: 16) {
                     Image(systemName: "suitcase")
                         .font(.largeTitle)
-                        .foregroundColor(.secondary)
+                        .foregroundStyle(Theme.textMuted(colorScheme))
                         .accessibilityHidden(true)
 
                     Text("No Saved Trips")
                         .font(.headline)
+                        .foregroundStyle(Theme.textPrimary(colorScheme))
 
                     Text("Browse featured trips on the Home tab or create your own to get started.")
                         .font(.subheadline)
-                        .foregroundColor(.secondary)
+                        .foregroundStyle(Theme.textSecondary(colorScheme))
                         .multilineTextAlignment(.center)
                 }
                 .frame(maxWidth: .infinity)