improvement: update llm utility methods

[overtonch]

Before this PR

The LLM utils:

1. Did not have docs indicating that they are intended for usage with the official provider SDKs. This is important since the URLs returned by the various utils may not work with clients from other SDKs (e.g., Vercel) if their client expects the URL in a different format, even for the same model.
2. Did not expose the gateway base URL method to users despite it being required if they need to construct custom URLs for use with other provider SDKs
3. Did not strip an extra https:// from the beginning of the context var which is present in some environments, leading to connection failures when trying to call a URL starting with https://https://

After this PR

==COMMIT_MSG==
Updates the LLM utility methods
==COMMIT_MSG==

Possible downsides?

None

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Type (Select exactly one)

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• Improvement (Improving existing functionality)
• Fix (Fixing an issue with existing functionality)
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• Migration (Automatically moving data/functionality to a new system)

Description

Updates the LLM utility methods

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[bryantpark04]

do all callers of this method handle the non-prefixed hostname as well?

[overtonch]

the only callers today are in this file, and they already are assuming no scheme is present and prepend https://

[bryantpark04]

language_models/utils.py was created by excavator PR #324. Are we sure this isn't one of our generated files that has to be updated upstream in python-platform-sdk?

[overtonch]

Thanks for checking me, I actually put them in the wrong place.

These are a special case where we add them to the assets directory and then have entries in config.json that copy them over into the generated package after generation is re-run