Add decentralized GenAI backend

[L-jasmine]

Relates to:

Risks

low risk. Add a new GenAI backend without affecting the functionality of other parts.

Background

Gaia is a decentralized AI agent network that allows users to run GenAI models and proprietary knowledge bases on their own computers. Gaia domains provides API services that are fully compatible with OpenAI and supports LLM, voice-to-text, image-to-text and text-to-voice models.

What does this PR do?

In this PR, I would like to add options for Eliza to choose Gaia nodes and domains as it’s backend GenAI services.

What kind of change is this?

Features: Add a GenAI backend

Documentation changes needed?

Because a new ModelProviderName was added, the references related to types in the docs automatically moved down by 2 lines. They are automatically generated by pnpm build.

If a docs change is needed: I have updated the documentation accordingly.

Testing

Where should a reviewer start?

Detailed testing steps

change .env to use gaianet node.

...
GAIANET_MODEL=qwen72b
GAIANET_SERVER_URL=https://qwen72b.gaia.domains/v1/info
GAIANET_EMBEDDING_MODEL=nomic-embed
USE_GAIANET_EMBEDDING=TRUE
...

The other parts are the same as usual.

[odilitime]

LGTM, a couple things we can improve later on with supporting multiple models/embeddings in the future, but no reason to hold this back though.