[Doc] Add encoder-based models to Supported Models page

[DarkLight1337]

Add encoder-only and encoder-decoder models to the list of supported models.

@maxdebayser I just realized we still don't have examples for offline inference using Score API. Can you add this in another PR? Also, should we rename it to Scoring API to be consistent with the word form of the other online APIs?

[github-actions]

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[youkaichao]

thanks for the efforts!