Unified Framework for Multi-Providers support

[enricoros]

We need a unified framework/protocol/practices for having different services implementable by different backends.

Such services include:

• search: Google, DuckDuckGo, Exa, etc.
• voice: OpenAI, ElevenLabs, Play.ht, Heygen, Wellsaid, Web Speech API
• speech reco: OpenAI, opensource whisper, whisper in AI services, Web Speech API
• image generation: OpenAI, Prodia (cheap stable diffusion), many many more...
• code execution: E2B, Google Code Execution (impl in Big-AGI 2.0), Google Colab API, ...

We'd benefit from a strategy and a framework to allow for configuration, auto-detection, auto-selection of the best, user configuration and overrides.

What we need:

• a prototype architecture which works for any implementation
• a strategy for selection of a common feature interface, or a superset of features, across a category
• a way for the user to configure each service (could be specific, but better if shared and stored uniformly)
• a way for the user to override configurations on a x_project, x_chat, x_something_else, dynamic and stored
• a way for the system to auto-select the best implementation, and update the selection if a better implementation becomes available (or if the user has altered the selection)

Originally posted by @enricoros in #614 (comment)