fix(agents): granite agent fixes, update granite docs and examples

[michael-desmond]

Which issue(s) does this pull-request address?

1. Granite example agents now have their own folder (examples/granite)
2. Moved the granite docs from the /docs to to a README.md inside of examples/granite so we can link directly to the README and the code examples (cookbook)
3. Added another example granite agent using retrieval with the wikipedia tool and updated documentation
4. Fixed an issue where default runner was not picking up templates from the templates method, and thus could not be over ridden in the granite runner subclass
5. Updates to granite system prompt (simplification), added time + date into the system prompt
6. Custom granite user template (remove createdAt) and custom granite tool prompts
7. Fixed an issue where the granite available tools were being double json encoded
8. Added an embedding example
9. Added a cosine similarity helper function

Checklist

• I have read the contributor guide
• Linting passes: yarn lint or yarn lint:fix
• Formatting is applied: yarn format or yarn format:fix
• Unit tests pass: yarn test:unit
• E2E tests pass: yarn test:e2e
• Tests are included
• Documentation is changed or added
• Commit messages and PR title follow conventional commits

[grahamwhiteuk]

Just a few minor bits to clean up and think about in the README. I also wonder whether we need some explanation around why the tooling is configured the way it is.

[grahamwhiteuk]

It looks to me like all the original review points have been addressed. We need to get this one merged ASAP so that we can use the resulting repo in the creation of some demo materials. @Tomas2D would you be able to go ahead and do the merge as it stands now?

[Tomas2D]

Great work guys! 🚀