Cu 86ewfyjet Implement Timezone Support for Leitner Box Scheduling and User Settings

[navidshad]

🏷️ PR Title: Implement Timezone Support for Leitner Box Scheduling and User Settings

📋 Summary

This PR introduces timezone support to the Leitner box review scheduling system, ensuring review times are correctly handled across different user timezones. It also adds a user timezone setting and includes testing and fixes to the catch-up logic related to scheduling.

🔗 Related Tasks

#86ewfyjet - Implement timezone support for Leitner box review scheduling and display, add user timezone setting, and fix catch-up logic with testing

📝 Additional Details

• Added comprehensive tests for timezone handling in scheduling
• Fixed catch-up logic to correctly account for user timezones
• Enhanced user experience by allowing timezone configuration in user settings

📜 Commit List

b3f240e feat: #86ewfyjet Implement timezone support for Leitner box review scheduling and display.
2d3aef5 feat: #86ewfyjet Implement user timezone setting
bb7d155 fix(schedule): #86ewfyjet add timezone support testing and fix catch-up logic

[navidshad]

Task linked: CU-86ewfyjet Implement User Time Zone Support