Add pagination to ranking system

[kcprdev]

Description

Added pagination support to the leaderboard/ranking system to improve navigation and scalability for larger datasets.

Linked Issue

Fixes #35

Changes Made

• Added Previous and Next navigation buttons
• Added numbered page controls
• Added configurable rows-per-page selector (10, 25, 50)
• Added active page highlighting
• Added leaderboard statistics display (total users, current range, current page)
• Integrated pagination with existing search functionality
• Integrated pagination with Overall, Monthly, Weekly, and Daily tabs
• Improved usability for large ranking datasets

Type of Change

• Bug fix
• New feature
• UI/Visual update
• Documentation update
• Refactor

Testing

• Tested locally
• Tested on mobile viewport (if applicable)
• No console errors introduced

Test Cases Performed

• Verified page navigation using Previous and Next buttons
• Verified numbered page controls
• Verified rows-per-page selector (10, 25, 50)
• Verified active page highlighting
• Verified leaderboard statistics update correctly
• Verified search functionality works with pagination
• Verified Overall, Monthly, Weekly, and Daily tabs work correctly

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• My changes generate no new warnings or errors
• I have linked the relevant issue

Screenshots / Screen Recording

demo.mp4

Attached screenshots demonstrating:

• Pagination controls
• Active page highlighting
• Rows-per-page selector
• Leaderboard statistics display

[github-actions]

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