Adds a simple notification when cloning a repo using the integrated git
clone on Zed. Before this, the user had no feedback after starting the
cloning action.

Demo:


https://github.com/user-attachments/assets/72fcdf1b-fc99-4fe5-8db2-7c30b170f12f

Not sure about that icon I'm using for the animation, but that can be
easily changed.

Release Notes:

- Added notification when cloning a repo from zed