Replace deprecated statusBarColor with enableEdgeToEdge()

[Thogaruchesti-hemanth]

Title:
Replace deprecated statusBarColor with enableEdgeToEdge()

Description:

Hi team,

The Dice Roller app currently uses the deprecated
window.statusBarColor API in Theme.kt.

Current Issue:

• File: app/src/main/java/com/example/diceroller/ui/theme/Theme.kt
• Deprecated API: window.statusBarColor
• Causes Android Studio warnings
• Does not follow Material3 edge-to-edge best practices

Proposed Solution:

• Use enableEdgeToEdge() in MainActivity
• Remove deprecated statusBarColor usage from Theme.kt
• Keep proper status bar icon appearance

Benefits:

• Removes deprecation warnings
• Follows modern Material3 guidelines
• Improves learning quality for students

I have signed the CLA and would like to work on this.
Please let me know if this contribution is welcome.

Thank you!