fix(ios): iOS 13.0 compatibility and test app UI unification

Fixed iOS 13.0 compatibility issue in test harness by replacing Logger
(iOS 14+) with os_log (iOS 13+). Fixed build script to correctly detect
and sync Capacitor config from App subdirectory. Unified both Android
and iOS test app UIs to use www/index.html as the canonical source.

Changes:
- DailyNotificationBackgroundTaskTestHarness: Replace Logger with os_log
  for iOS 13.0 deployment target compatibility
- build-ios-test-app.sh: Fix Capacitor sync path detection to check
  both current directory and App/ subdirectory for config files
- test-apps: Update both Android and iOS test apps to use www/index.html
  as the canonical UI source for consistency

This ensures the plugin builds on iOS 13.0+ and both test apps provide
the same testing experience across platforms.

scripts/build-ios-test-app.sh

@@ -174,12 +174,28 @@ build_ios_test_app() {
         fi
         
         # Sync Capacitor if needed
-        if command -v npx &> /dev/null && [ -f "capacitor.config.ts" ] || [ -f "capacitor.config.json" ]; then
+        # Check for config in current directory or App subdirectory
+        CAP_CONFIG_DIR=""
+        if [ -f "capacitor.config.ts" ] || [ -f "capacitor.config.json" ]; then
+            CAP_CONFIG_DIR="."
+        elif [ -f "App/capacitor.config.json" ] || [ -f "App/capacitor.config.ts" ]; then
+            CAP_CONFIG_DIR="App"
+        fi
+        
+        if command -v npx &> /dev/null && [ -n "$CAP_CONFIG_DIR" ]; then
             log_step "Syncing Capacitor..."
+            # Run sync from directory containing config
+            if [ "$CAP_CONFIG_DIR" != "." ]; then
+                cd "$CAP_CONFIG_DIR" || exit 1
+            fi
             if ! npx cap sync ios; then
                 log_error "Capacitor sync failed"
                 exit 1
             fi
+            # Return to ios/App directory if we changed
+            if [ "$CAP_CONFIG_DIR" != "." ]; then
+                cd .. || exit 1
+            fi
             log_info "Capacitor synced"
         fi
     fi