API Gateway for OpenAI Chat Sub-Process

### Overview 
- This workflow aims to provide data visualization capabilities to a native SQL Agent. 
- Together, they can help foster data analysis and data visualization within a team. 
- It uses the native SQL Agent that works well and adds visualization capabilities thanks to OpenAI’s Structured Output and Quickchart.io. 

### How it works 
1. Information Extraction: 
 - The Information Extractor identifies and extracts the user's question. 
 - If the question includes a visualization aspect, the SQL Agent alone may not respond accurately. 
2. SQL Querying: 
 - It leverages a regular SQL Agent: it connects to a database, queries it, and translates the response into a human-readable format. 
3. Chart Decision: 
 - The Text Classifier determines whether the user would benefit from a chart to support the SQL Agent's response. 
4. Chart Generation: 
 - If a chart is needed, the sub-workflow dynamically generates a chart and appends it to the SQL Agent’s response. 
 - If not, the SQL Agent’s response is output as is. 
5. Calling OpenAI for Chart Definition: 
 - The sub-workflow calls OpenAI via the HTTP Request node to retrieve a chart definition. 
6. Building and Returning the Chart: 
 - In the "Set Response" node, the chart definition is appended to a Quickchart.io URL, generating the final chart image. 
 - The AI Agent returns the response along with the chart. 

### How to use it 
- Use an existing database or create a new one. 
- For example, I've used [this Kaggle dataset]({{ $env.WEBHOOK_URL }} and uploaded it to a Supabase DB. 
- Add the PostgreSQL or MySQL credentials. 
- Alternatively, you can use SQLite binary files (check [this template]({{ $env.WEBHOOK_URL }} 
- Activate the workflow. 
- Start chatting with the AI SQL Agent. 
- If the Text Classifier determines a chart would be useful, it will generate one in addition to the SQL Agent's response. 

### Notes 
- The full Quickchart.io specifications have not been fully integrated, so there may be some glitches (e.g., radar graphs may not display properly due to size limitations).