- reduce the number of API keys needed (Use simple tool)
- make everything "tool use" oriented rather than split across agent executor, function calling, tool use, etc.
- Reorg navbar and index
- Fixup some docstrings
- Add more links to ref docs
- Mix up models used
- Simplify a few examples
- fix bug when using at=END_OF_RUN together with interrupt_before
- fix bug when calling update_state after only node has run
- update some notebooks to new streaming format (ie. no __end__ node)