Posthog

1. Add support for tool calls in OpenAI and Anthropic.
2. Add support for cached tokens.

1. Improve quota-limited feature flag logs

1. Add support for Azure OpenAI.

1. The LangChain handler now captures tools in `$ai_generation` events, in property `$ai_tools`. This allows for displaying tools provided to the LLM call in PostHog UI. Note that support for `$ai_tools` in OpenAI and Anthropic SDKs is coming soon.

1. feat: add some platform info to events (198)

1. Fix async client support for OpenAI.