Enhanced chatbot and QA Bot with retrievers (query fusion) and reranker (mmr reranker) and Switch default vector store to Weaviate

[patel-lyzr]

Description

What:
Why:
How:

What type of PR is this?

• 🎁 New feature (non-breaking change which adds functionality)
• 🐛 Bug fix (non-breaking change which fixes an issue)
• 💣 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📝 Documentation update
• 🎨 Refactor or style update
• 🔥 Performance improvements
• ✅ Test
• 🤖 Build
• 🔁 CI, review, release, devops, chore, etc.

Added tests?

• ☑️ Yes
• ❎ No, and this is why:
• ❓ No, because I need help.

How can this be tested?

Test A

• Description:
• Test Configuration:
• Test Instructions:
• Libraries:
• Expected Result:

[optional] Are there any post-deployment tasks we need to perform?

Checklist:

• 😎 My code follows the style guidelines of this project.
• ☑️ I have performed a self-review of my code.
• 📑 I have commented my code, particularly in hard-to-understand areas.
• 🔖 I have made corresponding changes to the documentation.
• ⚠️ My changes generate no new warnings.
• 🧐 I have added tests that prove my fix is effective or that my feature works.
• ✅ New and existing unit tests pass locally with my changes.
• 🔗 Any dependent changes have been merged and published in downstream modules.

Required links:

• Linear Issue:
• Testing Notebook (Colab):
• Code Documentation (Confluence):
• User Documentation (Confluence):

Contributors: