Added an example for LLM stack components

[zilto]

[Short description explaining the high-level reason for the pull request]
Could add further features with answer generation!

Changes

How I tested this

Notes

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.

[skrawcz]

Just a few changes and this is good to go! Thanks for the examples!

1. Add DAG images to README (and code to produce it).
2. Rebase this off of main, and put it in the new folder LLM_workflows
3. Can you rename the example directories to something like "blog_to_vector_db" and "modular_llm_stack"?
4. I left comments/suggestions otherwise.

[skrawcz]

Looks good. Just need to add instructions in the README for how to run things, and where to put API keys, etc.

[skrawcz]

Three changes:

• spell out how to run docker container
• provide example command line to cut and paste to run with weaviate
• move this example to be in the same directory as the LLM_Workflows folder - do this as your last commit independent of the changes above, e.g. git mv modular_llm_stack LLM_Workflows/modular_llm_stack.