Docs: Fix incorrect file download example in README for remote deployment

[arrrshia]

What was the problem?

The file download example in the README.md for remote deployment was not working as intended. The code iterated over the keys of the status["files"] dictionary (which are file hashes), and incorrectly passed them as filenames to the download_file() function.

This bug caused the script to download empty files that were incorrectly named after their file hashes, instead of downloading the actual stem file content with the correct filename.

How does this PR fix it?

This PR updates the code example to use the correct logic for downloading files:

It now iterates over status["files"].items() to correctly access both the file hash and the filename.

It replaces download_file() method with the correct download_file_by_hash() method.

This change ensures the example code is functional and correctly downloads the stem files as expected.

Code Changes

        for filename in status["files"]:
            output_path = api_client.download_file(task_id, filename)
            print(f"Downloaded: {output_path}")

is now

        for filehash, filename in status["files"].items():
            output_path = api_client.download_file_by_hash(task_id, filehash, filename)
            print(f"Downloaded: {output_path}")

[beveradb]

Cheers, sounds reasonable to me! This modal deployment script was really intended just as an example to get folks started, I don't actually use it myself so apologies for the bug and thanks for fixing 🙇