feat: add KEEP_MONITOR_AFTER_EXIT option to preserve tmux session after loop exits

[DrumRobot]

Description

After #176 was fixed, the tmux session is automatically terminated when the Ralph loop exits. This is good default behavior, but sometimes users want to keep the monitor panes alive after the loop finishes to review the final status, logs, and Claude output.

Use Case

• Review the last status dashboard and Claude output after Ralph completes
• Inspect tail -f live.log output for debugging without re-opening files
• Keep the tmux session as a reference while working on follow-up tasks

Proposed Solution

Add a KEEP_MONITOR_AFTER_EXIT config option (default: false) that skips the tmux kill-session chain when set to true.

.ralphrc usage:

KEEP_MONITOR_AFTER_EXIT=true

Behavior:

• false (default): Current behavior — entire tmux session terminates when loop exits
• true: Ralph pane shows exit message, but tail -f and status monitor panes remain active. User can manually close with tmux kill-session.

Implementation:

• Add default variable: KEEP_MONITOR_AFTER_EXIT="${KEEP_MONITOR_AFTER_EXIT:-false}"
• Conditional in setup_tmux_session(): branch on the config value

This is a minimal 2-line change that preserves the #176 fix as the default.

[coderabbitai]

🔗 Related PRs

#90 - fix(loop): respect Claude's EXIT_SIGNAL when checking completion indicators [merged]
#177 - fix: auto-terminate tmux session when Ralph loop exits [merged]
#179 - fix(loop): prevent silent script death on Claude timeout [merged]

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[github-actions]

Thanks for the well-detailed feature request, @DrumRobot! 🎉

Triage: Enhancement — This has been labeled as an enhancement request.

Summary: You're proposing a KEEP_MONITOR_AFTER_EXIT config option (defaulting to false) that preserves the tmux session after the Ralph loop exits, rather than auto-terminating it. This keeps the default behavior from #176 intact while giving users who want to review post-run output the option to do so.

Recommended next steps:

• The implementation looks straightforward as described (adding a default variable + a conditional branch in setup_tmux_session()).
• A PR with the change and a corresponding test in the unit test suite would be welcome.
• Consider also supporting a --keep-monitor CLI flag as an alternative to the .ralphrc config for one-off use.

Generated by Issue Triage Assistant for issue #213