Fix remaining 17 UI test failures: group defaults, identifiers, hittability, date format

- resetAppState: use correct suite name to clear group defaults (fixes stale subscription state)
- Reorder configureIfNeeded: set expireTrial before IAPManager init
- Add browse_themes_button identifier to CustomizeView Browse Themes button
- Add mood_button_* identifiers to Entry Detail mood grid in NoteEditorView
- Use coordinate-based tap throughout all test screens (iOS 26 Liquid Glass hittability)
- Fix HeaderMoodLogging date format: M/d/yyyy → yyyy/MM/dd to match entry_row identifiers
- AppLaunchTests: wait for isSelected state with NSPredicate instead of immediate check
- OnboardingTests: add waits between swipes and retry logic for skip button

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

Tests iOS/HeaderMoodLoggingTests.swift

@@ -25,7 +25,7 @@ final class HeaderMoodLoggingTests: BaseUITestCase {
 
         // 4. Verify an entry row appeared for today's date
         let formatter = DateFormatter()
-        formatter.dateFormat = "M/d/yyyy"
+        formatter.dateFormat = "yyyy/MM/dd"
         let todayString = formatter.string(from: Date())
 
         dayScreen.assertEntryExists(dateString: todayString)