hermes - 💡(How to fix) Fix Terminal backend (local) reports inconsistent `crontab -l` output compared to user shell (same UID)

Summary

With terminal.backend: local on macOS, Hermes appears to execute shell commands as the same user as the invoking shell, but crontab -l returns a different result when run through Hermes vs. when run directly in the user's terminal. This suggests either the command is not actually being executed, or its stdout is not faithfully captured/propagated by the terminal tool.

Environment

• OS: macOS (Apple Silicon, MacBook Pro)
• Shell: zsh
• Hermes config (~/.hermes/config.yaml):

terminal:
  backend: local
  modal_mode: auto
  cwd: .
  timeout: 180

Steps to reproduce

1. In the user shell, create a simple user crontab entry, e.g.:

   0 20 * * * /Users/<user>/backup_test.sh >> /Users/<user>/backup.log 2>&1

2. In the user shell run:

   whoami
   id
   echo $USER $LOGNAME $HOME
   crontab -l

3. In a Hermes session (same machine, same user), ask the agent to run the exact same commands via its terminal tool.

Expected behavior

Since both processes run as the same UNIX user with the same $HOME, crontab -l should return identical output in both contexts.

Actual behavior

• whoami, id, echo $USER $LOGNAME $HOME match exactly between the user shell and Hermes (same user marco, uid 501, $HOME=/Users/marco).
• crontab -l in the user shell correctly prints the configured cron entry.
• crontab -l executed through Hermes returns no crontab for marco (i.e. empty), despite running as the same user on the same host.

Additional notes

• Attempting to install a shell wrapper around /usr/bin/crontab to verify whether Hermes actually invokes the binary is not possible on recent macOS because /usr/bin is on the Signed System Volume and mv/tee fail with Operation not permitted even under sudo.
• Interactive TUI commands (e.g. crontab -e, vim) are also refused by the agent, which may be by design, but the inconsistency on the non-interactive crontab -l is unexpected.

Impact

Users cannot rely on Hermes' reported output for system-level commands (cron, backups, permissions) when using backend: local on macOS, because the observed output diverges from the ground truth visible in a normal shell.

Possible causes to investigate

• The terminal tool may not be actually executing the command and is instead synthesizing the output.
• A bug in stdout capture / PTY handling for specific binaries like crontab.
• Environment differences (e.g. a modified PATH or sandboxing) that cause a different crontab binary to be invoked.