Send ChatGPT Ads conversions as standard events (lead_created) for campaign optimization

The issue: the ChatGPT Ads integration sends events as custom events (cr_call, cr_form_submission, cr_sms_received). OpenAI's documentation states that custom events cannot be used for conversion optimization; conversion-optimized campaigns require a standard event. As a result, we can report on CallRail conversions in Ads Manager, but we can't select them as the optimization goal for our campaigns.

The request: Add an option to send calls and form submissions as OpenAI's standard lead_created event, ideally with a per-event mapping setting similar to the Google Ads integration.