Add vscode via vendor package.

- Use yarn for vscode vendoring.
- Grab hash from package.

ci/dev/fmt.sh

@@ -19,7 +19,7 @@ main() {
     "*.sh"
   )
   prettier --write --loglevel=warn $(
-    git ls-files "${prettierExts[@]}" | grep -v "lib/vscode" | grep -v 'helm-chart'
+    git ls-files "${prettierExts[@]}" | grep -v "lib/vscode" | grep -v "vendor/modules/code-oss-dev" | grep -v 'helm-chart'
   )
 
   doctoc --title '# FAQ' docs/FAQ.md > /dev/null
@@ -32,6 +32,7 @@ main() {
   doctoc --title '# iPad' docs/ipad.md > /dev/null
   doctoc --title '# Termux' docs/termux.md > /dev/null
 
+  # TODO: replace with a method that generates fewer false positives.
   if [[ ${CI-} && $(git ls-files --other --modified --exclude-standard) ]]; then
     echo "Files need generation or are formatted incorrectly:"
     git -c color.ui=always status | grep --color=no '\[31m'