feat: improve ai chatbot prompt + ux 📈

[ramiAbdou]

Description ✏️

This PR:

• Doesn't emit the slack.chatbot.message if the DM is from a bot (ie: ColorStack app).
• Logs the Anthropic token usage after a chat completion.
• Updates the createDatabaseConnection to accept an optional database URL as an argument.
• Improves the UX of the AI chatbot:
  • First checks whether or not the input is a question and if it's not, says "can't answer this".
  • Then, immediately sends a "Searching our Slack history..." message.
  • Updates the linked thread presentation (uses the [1] as an example).
  • Uses the top 5 most similar messages in the Pinecone query.
  • The prompt now takes into account the creation date + score of the match.
• Additionally, the max tokens is 1000.

Type of Change 🐞

• Feature - A non-breaking change which adds functionality.
• Fix - A non-breaking change which fixes an issue.
• Refactor - A change that neither fixes a bug nor adds a feature.
• Documentation - A change only to in-code or markdown documentation.
• Tests - A change that adds missing unit/integration tests.
• Chore - A change that is likely none of the above.

Checklist ✅

• I have done a self-review of my code.
• I have manually tested my code (if applicable).
• I have added/updated any relevant documentation (if applicable).