feat: added animation

[urastogi2048]

Description

This pull request adds visual polish and interaction improvements to the Start Menu.
Enhancements include:

• Animated background (subtle soft motion loop to replace static blue background)
• Animated logo entrance
• Button hover and click scale animations
• Fade-in when menu loads and fade-out when changing scenes (SceneFader)

These changes make the main menu visually appealing and more dynamic while remaining performance-friendly and within the scope of simple UI animations.

Semver Changes

• Minor (new features, no breaking changes)

Issues

Closes #52

Checklist

• I have read the Contributing Guidelines.
• UI animations are lightweight and follow the existing art style
• Scene transitions use simple fade, no additional packages added
• No gameplay logic modified

[Just-Here-TO-Code]

@urastogi2048
This animation can be improved..? Please see to it, closing for now.