fix: Improve reliability of Orchestrator downloader

[taicchoumsft]

Description

The Orchestrator language model downloader did not properly catch exceptions in Orchestrator.baseModelGetAsync. This would lead to the download notification spinning endlessly if the language model download fails in some cases, though it can be dismissed.

This PR propagates the error messages by forwarding errors with >400 status codes. This will be caught by the axios promise rejection in the frontend, and a notification failure with the error message will be shown if the download fails.

Task Item

#minor

[coveralls]

Coverage decreased (-0.02%) to 51.655% when pulling c1e3152 on tachou/orchImproveDownloader into 4774755 on main.

[hatpick]

nit: type is a reserved keyword, I suggest using somethingType or kind

[taicchoumsft]

Thanks @hatpick , I was using the convention that others used here. Is interface ok?

[hatpick]

I meant the key you use here, type, in strict mode it will complain about it but I guess we are not in that mode. It's still a good practice if you replace it with somethingType or kind:
type: 'en_intent' | 'multilingual_intent';

[taicchoumsft]

Ah ok understood thanks, will change to kind.

[taicchoumsft]

Changed to kind here, enclosed the orchestrator controller in a class, added all other requested changes. Thanks @hatpick