* docs: add LiteLLM proxy setup guide
Document the setup process for LiteLLM and its integration with OpenClaude, including prerequisites, configuration, and troubleshooting steps.
* Revise LiteLLM setup steps for Adocs: fix /provider walkthrough to match actual OpenAI-compatible flowPI key and model
Updated setup instructions for LiteLLM provider configuration.
* docs: fix sub-bullet formatting in /provider steps
* docs: clarify key scope in troubleshooting (LiteLLM proxy process env)
Clarified instruction for upstream provider error regarding API key.
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