This adds two convenience scripts:
- update-vscode.sh downloads/updates Visual Studio Code
- update-compile-commands.py prepares for code indexers like clangd
  by creating compile_commands.json (for all architectures), updating
  generated sources, and compiling the Torque Language Server.

No-try: true
Change-Id: I64a15dc298f4312a9b296762593234c40f542b06
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2317355
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69105}