feat: add analytics export system with CSV and JSON support

[puneetnith28]

Feature: Export Analytics System

Summary

This PR introduces a complete analytics export system for the BrowsePing extension, enabling users to download their browsing analytics in CSV and JSON formats directly from the UI.

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Key Features

• CSV and JSON export support
• Section-wise exports:
  • Tab Usage
  • Hourly Presence
  • Leaderboard
• Centralized Data Management page under More Settings
• One-click Export All for cumulative analytics
• Smart file naming with timestamps
• Toast notifications and loading states
• Fully client-side, privacy-first implementation

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Privacy & Security

• All data is processed locally in the browser
• No analytics data is sent or stored externally
• Users have full control over when and what to export

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Screenshots

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Closes #4

[puneetnith28]

Hello @akash-kumar-dev
Please review this PR and let me know if any changes are required.
Thanks !!

[akash-kumar-dev]

Hi @puneetnith28 , great work! Could you open a new PR with a new branch, incorporating these changes:

• Keep the export button only in the Tab Usage and Hourly Presence sections of the analytics window. Do not add it to the Leaderboard tab.
• Remove Data Management from the More Settings page; there's no need to add this feature there.
• Only keep the export option in the Tab Usage and Hourly Presence tabs.

[puneetnith28]

Hi @puneetnith28 , great work! Could you open a new PR with a new branch, incorporating these changes:

• Keep the export button only in the Tab Usage and Hourly Presence sections of the analytics window. Do not add it to the Leaderboard tab.
• Remove Data Management from the More Settings page; there's no need to add this feature there.
• Only keep the export option in the Tab Usage and Hourly Presence tabs.

Hello @akash-kumar-dev
Thanks for the review and feedback!
I’ve opened a new PR with a refined scope as suggested and will close this one to keep things clean.