Add extension support to Co-pilot button and sidebar

[jack-atakama]

Currently, the Microsoft Edge Co-pilot button and sidebar do not support extensions. This limits developers and users from enhancing the sidebar experience with custom functionality. Adding extension support would enable developers to integrate tools, workflows, and third-party services directly into the Co-pilot sidebar, providing richer and more tailored experiences for users without leaving the Edge interface.

[Sunwuyuan]

Microsoft is willing to add Copilot to devtools , although it is almost unusable for programming, but unwilling to maintain a useful tool for quickly debugging network requests #348