CodeRabbit and Greptile both flagged the SSHConnPool: the executor never
took the pool path (CreateInstance always dialDirect'd a fresh client and
parked it on sshSessionState), so the pool's keepalive goroutines and
refcount logic were dead code. Get() also overwrote map entries on every
call, which would have leaked keepalive goroutines if the pool *had* been
used. Delete the entire SSHConnPool + sshConnKey + pooledConn + keepalive
plumbing. Export DialSSH so the SSH test endpoint can dial directly and
close the client when its single-shot probe is done.
While here:
* pickRemoteAgentctlPort: switch from time.Now().UnixNano()%20000 to
math/rand/v2.IntN. Two concurrent CreateInstance calls on a fast
machine were getting the same port (UnixNano cycles in ~20µs through
the 20k range); randomized picks avoid the collision.
* createRemoteAgentInstance: POST to the remote control port over a
direct-tcpip dial via net/http instead of shelling out to `curl`. The
sshd container no longer needs curl, the kandev test endpoint no
longer needs to probe for it, and the call inherits Go's standard
timeout + error handling. Drop `curl` from the e2e Alpine image.
* maybeUploadCredentials: was probing `printf %s "$HOME"` and
discarding the output, then allocating an unused sshFileUploader.
SSH v1 doesn't ship credential upload — just log a warning when a
user sets remote_credentials so they know it won't take effect, and
delete the dead uploader file.
José Almeida
a30833b336