fix: comprehensive codebase hardening — crashes, silent failures, performance, and security

Fixes ~95 issues from deep audit across 12 categories in 82 files:

- Crash prevention: double-resume in PhotoMetadataExtractor, force unwraps in
  DateRangePicker, array bounds checks in polls/achievements, ProGate hit-test
  bypass, Dictionary(uniqueKeysWithValues:) → uniquingKeysWith in 4 files
- Silent failure elimination: all 34 try? sites replaced with do/try/catch +
  logging (SavedTrip, TripDetailView, CanonicalSyncService, BootstrapService,
  CanonicalModels, CKModels, SportsTimeApp, and more)
- Performance: cached DateFormatters (7 files), O(1) team lookups via
  AppDataProvider, achievement definition dictionary, AnimatedBackground
  consolidated from 19 Tasks to 1, task cancellation in SharePreviewView
- Concurrency: UIKit drawing → MainActor.run, background fetch timeout guard,
  @MainActor on ThemeManager/AppearanceManager, SyncLogger read/write race fix
- Planning engine: game end time in travel feasibility, state-aware city
  normalization, exact city matching, DrivingConstraints parameter propagation
- IAP: unknown subscription states → expired, unverified transaction logging,
  entitlements updated before paywall dismiss, restore visible to all users
- Security: API key to Info.plist lookup, filename sanitization in PDF export,
  honest User-Agent, removed stale "Feels" analytics super properties
- Navigation: consolidated competing navigationDestination, boolean → value-based
- Testing: 8 sleep() → waitForExistence, duplicates extracted, Swift 6 compat
- Service bugs: infinite retry cap, duplicate achievement prevention, TOCTOU vote
  fix, PollVote.odg → voterId rename, deterministic placeholder IDs, parallel
  MKDirections, Sendable-safe POI struct

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

SportsTime/Export/PDFGenerator.swift

@@ -811,6 +811,15 @@ final class ExportService {
     private let pdfGenerator = PDFGenerator()
     private let assetPrefetcher = PDFAssetPrefetcher()
 
+    /// Sanitize a string for use as a filename by removing invalid characters.
+    private func sanitizeFilename(_ name: String) -> String {
+        let invalidChars = CharacterSet(charactersIn: "/\\:*?\"<>|")
+        return name.components(separatedBy: invalidChars).joined(separator: "_")
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+            .prefix(255)
+            .description
+    }
+
     /// Export trip to PDF with full prefetched assets
     /// - Parameters:
     ///   - trip: The trip to export
@@ -839,7 +848,8 @@ final class ExportService {
         )
 
         // Save to temp file
-        let fileName = "\(trip.name.replacingOccurrences(of: " ", with: "_"))_\(Date().timeIntervalSince1970).pdf"
+        let safeName = sanitizeFilename(trip.name)
+        let fileName = "\(safeName)_\(Date().timeIntervalSince1970).pdf"
         let url = FileManager.default.temporaryDirectory.appendingPathComponent(fileName)
 
         try data.write(to: url)
@@ -859,7 +869,8 @@ final class ExportService {
             itineraryItems: itineraryItems
         )
 
-        let fileName = "\(trip.name.replacingOccurrences(of: " ", with: "_"))_\(Date().timeIntervalSince1970).pdf"
+        let safeName = sanitizeFilename(trip.name)
+        let fileName = "\(safeName)_\(Date().timeIntervalSince1970).pdf"
         let url = FileManager.default.temporaryDirectory.appendingPathComponent(fileName)
 
         try data.write(to: url)