Ubuntu repository setup does not fail safely

The Ubuntu setup script adds external APT repositories and their signing keys, but the individual commands used to configure them are not consistently checked for failure.

For example, repository setup involves commands such as:

curl -fsSL ... | sudo gpg --dearmor ...

followed by writing the repository configuration.

If downloading the signing key or writing the repository configuration fails, the script may continue instead of stopping or clearly reporting that the repository setup failed.

This can result in a later apt-get update or package installation failure that does not clearly indicate the original cause.

This makes troubleshooting more difficult and can leave the system in a partially configured state.

For example:

1. The signing key download fails.
2. The script continues.
3. The repository configuration is still written.
4. A later package installation fails.
5. The user sees a package installation error rather than the actual repository/key setup failure.

This is especially problematic because the repository setup is a prerequisite for installing packages such as Google Chrome or Visual Studio Code.

Start with the Ubuntu setup script and locate the repository setup entry point, including the curl|gpg pipeline and repository configuration writes. Trace how failures are handled before the later apt-get update or package installation steps. Done means signing-key or repository-configuration failures stop the setup or are clearly reported instead of allowing later package operations to mask the cause.