Added new interactive themes and CSS-only tooltips for enhanced user experience

[aryaman108]

This PR introduces three new features to Starability.css that enhance interactivity and accessibility without adding any JavaScript dependencies:

New Features

1. starability-glow Theme

   • Adds smooth scaling (1.1x) and golden glow effects on hover
   • Provides visual feedback with CSS transitions
   • Maintains the library's lightweight, CSS-only approach

2. starability-pulse Theme

   • Implements a subtle pulsing animation on hover
   • Creates dynamic feedback for user interactions
   • Uses CSS keyframes for smooth performance

3. CSS-Only Tooltips

   • Adds hover and focus tooltips using data-tooltip attributes
   • Improves accessibility for keyboard navigation
   • No JavaScript required - pure CSS implementation

Advantages

• Zero Performance Impact: All features are CSS-only, maintaining the library's core principle of no JavaScript dependencies
• Enhanced Accessibility: Tooltips work with keyboard navigation and screen readers
• Backward Compatible: Existing implementations remain unchanged
• Easy to Use: Simple class changes and attribute additions
• Consistent with Library Design: Follows existing SCSS patterns and variables

Labels Requested: enhancement, feature, accessibility, documentation, css