Custom Date and Time Format Support

Description Currently, the date and time display formats in OneCalendar (e.g., Week view, Month view, Event details) are often fixed or dependent on system settings. I would like to request a feature that allows users to manually choose their preferred date and time format within the app's settings. Rationale (Why this is needed) Better Readability: Date format preferences vary significantly by region and personal habit (e.g., YYYY/MM/DD vs. DD/MM/YYYY). Consistency with Business Tools: Many users use OneCalendar alongside other professional tools. Having the ability to match formats reduces cognitive load and data entry errors. Platform Independence: While the app currently respects some system settings, having a dedicated toggle within the app ensures a consistent experience across Windows, Android, and iOS. Proposed Features / Changes Add a "Date & Time Format" section under the Settings menu with the following options: Date Format Options: 2026/03/21 (YYYY/MM/DD) 21/03/2026 (DD/MM/YYYY) 03/21/2026 (MM/DD/YYYY) Mar 21, 2026 (Month name format) Time Format Options: 24-hour clock (e.g., 14:00) 12-hour clock (e.g., 2:00 PM) Expected Impact These changes should be reflected in: Headers in all views (Day/Week/Month/Year). The "Create/Edit Event" input fields. Widgets (iOS, Android, and Windows). Push notifications. Additional Notes As OneCalendar is a multi-platform app, it would be ideal if these format preferences were synced across all devices linked to the same account.