Howdy, RStudio and Posit Workbench PM here 
:
Ultimately, as Randy mentions, Posit doesn't control the data here, it's being sent to GitHub servers. Support and Terms of Service. Each team needs to evaluate their comfort level with external APIs, whether for data storage, processing, or GenAI purposes.
However, we do our best to avoid sending known sensitive data. The Copilot feature targets source files, and we exclude common environment files (ie .Renviron) and do not attempt to index data files.
I have worked with regulated industry customers (pharma, finance, banking, insurance, etc) who are bringing their own LLMs to bear and need to ensure data never leaves their environment, even if it would otherwise be fine to use an enterprise-grade GenAI tool.
One approach is chattr: Interact with Large Language Models in RStudio • chattr which allows for local on workstation LLMs via tools like Ollama. This gives you a chat interface and GenAI with custom prompting but removes the "assumed risk" of sending data outside of your local environment.
Alternatively, other teams are using the .rs.api.setGhostText() API in RStudio + an RStudio add-in to add their own GenAI tooling as a "copilot".