fix: add ssh -t to zsh alias, use vterm-mode instead of vterm in Emacs function

- zsh alias: added -t to SSH (docker exec -it needs a TTY)
- Emacs function: vterm-mode instead of vterm (vterm splits windows,
  vterm-mode is just a major mode, keeps current window layout)
- The SSH command in both cases is now consistent:
  ssh -t lazyworkhorse 'docker exec -it hermes /opt/hermes/.venv/bin/hermes'

zsh/.zshrc

@@ -20,7 +20,7 @@ alias emacs="emacsclient -c -a emacs"
 alias oc="opencode"
 
 # Hermes Agent - SSH directly to remote server
-alias hermes="ssh lazyworkhorse 'docker exec -it hermes /opt/hermes/.venv/bin/hermes'"
+alias hermes="ssh -t lazyworkhorse 'docker exec -it hermes /opt/hermes/.venv/bin/hermes'"
 
 # Yazi
 alias y="yazi"