Version: 2026.04.27.00.58

Implement Business/Personal mode separation and Material 3 UI overhaul

• Implemented distinct Personal and Business account modes with unique color schemes (Teal for Personal, Indigo for Business) and metadata.
• Redesigned the Calendar screen with support for multiple view modes: Agenda, Day, 3-Day, Week, and Month.
• Overhauled the Settings screen with categorized sections, profile picture support, and expanded fields for personal and employer data.
• Added an account switcher in the AppTopBar to toggle between Personal and Business contexts.
• Refactored Task and Appointment editing with grouped sections, modern input styles, and account-specific labels (e.g., "Team" vs "Friends").
• Enhanced the GreetingOverlay with automated messages for birthdays, Christmas, and Easter.
• Implemented a tabbed view in the Tasks screen to separate private and business duties, including swipe-to-dismiss deletion and expandable completed sections.
• Expanded ThemePreferences and SettingsViewModel to manage new configuration keys for holidays, travel time, and calendar visibility.
• Improved AppointmentCard and TaskItem components with status icons for priority, business type, and confirmation status.
• Integrated a new Typography system and updated all screens to use TopAppBar scroll behaviors and consistent M3 surface containers.