[Misc] Rename env in runtime

[brosoul]

Pull Request Description

Rename env name to add DOWNLOADER_ prefix name

Related Issues

Resolves: #[Insert issue number(s)]

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[Jeffwan]

@brosoul please rebase the main and update the PR.

[brosoul]

@brosoul please rebase the main and update the PR.

done

[brosoul]

After discussion, we have decided to manage variable names by adding prefixes such as DOWNLOADER_ before the original environment as variable names.