[Feature]: Progress bars for data downloads and backtests

[Satvik-Singh192]

So, what is it about?

Add tqdm-based progress bars for long-running operations like data downloads and backtests.

This feature will improve the user experience by providing real-time feedback during potentially time-consuming processes, such as fetching price data or iterating over backtest bars.

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Code of Conduct

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[Satvik-Singh192]

@ayushkrtiwari please assign this issue to me

[ayushkrtiwari]

you have been assigned this issue @Satvik-Singh192

[Satvik-Singh192]

@ayushkrtiwari please review my latest PR sir