This makes sure that if folks get a relatively recent `vscode.d.ts`. It also lets us safely bump up the target to es2024 so you can use all the latest lib additions
Fixes#180
Changes from using `vscode` to `@types/vscode` for the majority of extension samples. The `@types/vscode` package is much smaller and does not pull in any dependencies.
Other changes:
- Remove so empty test files
- Bump engine versions to match @types/vscode versions
- Use `npm run compile` for most `vscode:prepublish` scripts
