**Problem**
All of our extensions currently are built using the dom typings. This can lead to runtime errors if you mistakenly use `window` or similar
**Fix**
Exclude the dom typings from compile. Then explicitly import the node types for `URL` and `TextEncoder`
Fixes#86389Fixes#86776
Uses `fs.stat` to check if we are showing an untracked image in the git diff view.
Also required fixing `stat` for `gitfs` so that it can try to return the proper sizes for objects
