add docker compose ollama

[hitpoint6]

Please describe the purpose of this pull request.
Is it to add a new feature? Is it to fix a bug?

• Enable running Letta with ollama powered model with one command

How to test
How can we test your PR during review? What commands should we run? What outcomes should we expect?

1. Run the containers: export LETTA_LLM_MODEL=llama3; docker compose -f docker-compose-ollama.yaml up --remove-orphans. Replace llama3 with your own model id`
2. Once the container is running, pull a model by running the docker exec -it ollama ollama run llama3. Replace llama3 with your model here.
3. Open http://localhost:8083/
4. Create an agent and chat with the agent. Note that the model running here is small so it is much less powerful than gpt-4o

Have you tested this PR?
Have you tested the latest commit on the PR? If so please provide outputs from your tests.

Yes, Able to create an agent and have conversations.

Related issues or PRs
Please link any related GitHub issues or PRs.

Is your PR over 500 lines of code?
If so, please break up your PR into multiple smaller PRs so that we can review them quickly, or provide justification for its length.

Additional context
Add any other context or screenshots about the PR here.