[Feature]: Use the user's SSH key in `dstack` CLI

[jvstme]

Problem

#2053 added support for user SSH keys managed by the dstack server. However, the CLI still uses ~/.dstack/ssh/id_rsa when applying runs, so the initial problem remains the same — users cannot attach to runs that they started from another machine.

Solution

Use server-managed SSH keys when starting new runs from the CLI.

Note

~/.dstack/ssh/id_rsa should still remain supported for compatibility with old runs and servers.

Workaround

Use dstack apply --ssh-identity ... to enable access to the run from different machines.

Would you like to help us implement this feature by sending a PR?

Yes