feat(digital-clock): add digital clock with modern UI

[kaiyumdev]

fix: #665

What does this PR do?

This PR introduces a new Advanced UI/UX Digital Clock application that provides users with an elegant and feature-rich time display solution. The implementation focuses on modern design principles and user experience best practices.

Key features include:

• Real-time clock display with automatic updates
• Dynamic greeting system based on time of day
• Week number and day of year tracking
• Light/dark theme toggle with smooth transitions
• Responsive design for all device sizes
• Accessibility considerations

Fixes #665

##Screenshots

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How should this be tested?

Functional Testing

• Test clock accuracy

  • Open the application in a browser
  • Compare displayed time with system time
  • Verify time updates every second
  • Check time format consistency (HH:MM:SS)

• Test date and additional info

  • Verify current date display accuracy
  • Confirm week number calculation
  • Validate day of year counting
  • Check greeting changes based on time of day (morning/afternoon/evening)

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