Fix: Update GPT model to resolve API validation error

Problem

The D-ID Agents API was returning a validation error when creating new agents:

{
    "kind": "ValidationError", 
    "description": "validation failed",
    "details": {
        "payload.llm": {
            "message": "Could not match the union against any of the items. Issues: [{\"payload.llm.model\":{\"message\":\"should be one of the following; ['gpt-35-turbo','gpt-4o-global','gpt-4o-mini']\",\"value\":\"gpt-3.5-turbo-1106\"}}]"
        }
    }
}

Root Cause

The code was using the deprecated GPT model gpt-3.5-turbo-1106, which is no longer supported by the D-ID API. The API now only accepts:

• gpt-35-turbo
• gpt-4o-global
• gpt-4o-mini

Solution

Updated the LLM configuration in the agentsAPIworkflow() function to use gpt-4o-mini instead of the deprecated model.

Changes

• File: agents-client-api.js
• Line: 472
• Change: model: 'gpt-3.5-turbo-1106' → model: 'gpt-4o-mini'

Testing

• ✅ Agent creation now works without validation errors
• ✅ Existing functionality remains unchanged
• ✅ No breaking changes to API

Impact

This fix resolves the "Create new Agent with Knowledge" functionality that was previously failing due to the outdated model configuration.

closes #68