Improvements: - Onboarding welcome screen is now shown only once and remembered across app restarts - Improved audio system reliability for completion sounds - now uses system audio services and properly respects device mute switch and volume settings - Enhanced screen keep-awake functionality to prevent unexpected sleep during checklist use, with better timer management - Automatic cleanup of abandoned checklists when returning to the template list (removes empty checklists you started but never completed any items) Bug Fixes: - Fixed issue where tapping notifications could create multiple active checklists