* [#444] added refresh on sync token calendar update
* [#444] added refresh on register and tests
* [#444] extracted logic for useEffects and updates
* [#444] refactored code structure to use absolute paths
- Display 2-letter initials (e.g., "JD" for "John Doe") instead of single letter
- Add getInitials helper function in avatarUtils for reusability
- Update Avatar in PeopleSearch, CalendarSearch, and Menubar components
- Remove avatarUrl prop usage across all Avatar components
* UI: #334 add config page language setting
* temporary remove logout button
* Unify fullscreen view class for dialog expanded and settings view
- Replace dialog-expanded and settings-view with single fullscreen-view class
- Update ResponsiveDialog to use fullscreen-view class
- Update CalendarLayout to use fullscreen-view class for settings view
- Consolidate CSS rules in Menubar.styl to use fullscreen-view
- Update test cases to use new class name
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Co-authored-by: Lê Nhân Phụng <lenhanphung@Phung-Mac-M4.local>