Add comprehensive SSH integration tests covering: - push creates repo on demand and clone round-trips match HEAD - push rejected when disabled, repo not created - clone of missing repository fails - receive-pack hooks fire asynchronously after push response Tests drive a real git client over ssh:// against an in-process SSH server backed by memfs, generating ephemeral ed25519 client keys and bypassing host key checking for CI environments. Helpers: gitSSHEnv() configures GIT_SSH_COMMAND and isolation env vars, gitWithEnv() runs git with custom env (callers can inspect errors), startSSHServer() creates an in-memory daemon on an ephemeral port. Assisted-by: Claude Sonnet 4.6 via Claude Code