Starlark - Support for SSH Host Key Check in ssh_config

[vladimirvivien]

Currently, the code ignores and does not validate host keys during an SSH/SCP operation. While this allows Crashd scripts to run quietly, it can be viewed as a security issue for production usage. This issue is a feature request to allow Crashd to control the host key check behavior. The host key check should be done by default. A flag should be provided for script writers to disable that behavior (useful in CI/CD or testing environment):

Skipping host key check

ssh_config(user="sshueser", hostkey_check=false)

A hostkey_check = true (default) means the SSH client will apply host key validation.