fix: more tolerance for ai response in opportunity creation ❗️

[ramiAbdou]

Description ✏️

This PR fixes a couple issues with the opportunity creation from Slack:

• Allows the company field to be null if the AI cannot determine the company name from text (happens when there is no mention of the company in the website text content).
• Fixes the ability to retry creation of an opportunity. Previously the on conflict do nothing would negate the returning statement, which meant the function would throw an error.
• Separates the JSON parsing from the Zod parsing, to be clearer about where the function failed. Also added some logs in case of failure.

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).