fix: propagate --sandbox flag through start/stop to Telegram bridge

[SARPAT]

Summary

• Export SANDBOX_NAME in start-services.sh so child processes (telegram-bridge) inherit it
• Parse --sandbox <name> in bin/nemoclaw.js start()/stop() and forward to the shell script via both env var and CLI flag
• Fall back to registry default when no --sandbox flag is provided

Fixes #198

Root cause

Two gaps in the env propagation chain:

1. bin/nemoclaw.js start()/stop() ignored CLI arguments — --sandbox was never parsed or forwarded
2. start-services.sh set SANDBOX_NAME as a local variable (not exported), so nohup node telegram-bridge.js never inherited it

How this differs from existing PRs

• fix: resolve sandbox name from registry in Telegram bridge #96: fixes the bridge only; doesn't address the CLI not forwarding --sandbox
• fix: telegram bridge sandbox name resolution and retry on SSH failures #139: fixes start-services.sh but bundles unrelated SSH retry + vLLM venv changes
• fix: propagate SANDBOX_NAME to telegram bridge and resolve openshell path #222: adds SANDBOX_NAME export but bundles unrelated openshell path resolution (Telegram bridge fails with "openshell: not found" because ~/.local/bin isn't on PATH for child processes #199)

This PR covers both gaps with minimal scope and includes tests.

Test plan

• npm test — 59 tests pass (includes new test/start-sandbox-flag.test.js)
• nemoclaw start --sandbox <name> → verify /tmp/nemoclaw-services-<name>/ PID dir + correct sandbox in bridge logs
• nemoclaw start with no flag → uses registry default

[brianwtaylor]

Hey @SARPAT — just flagging that #222 (filed ~3 hours earlier) already covers the #198 fix here. The export SANDBOX_NAME change and the CLI --sandbox forwarding are the same root cause fix.

#222 also addresses #199 (openshell path resolution in the bridge) which is part of the same propagation chain — the bridge fails on both missing SANDBOX_NAME and an unresolvable openshell binary when launched via nohup. Splitting them means a second PR touching the same files for a tightly coupled issue.

Happy to coordinate if maintainers prefer a different breakdown, but wanted to make sure the overlap is visible.

-BT

[SARPAT]

Hey @SARPAT — just flagging that #222 (filed ~3 hours earlier) already covers the #198 fix here. The export SANDBOX_NAME change and the CLI --sandbox forwarding are the same root cause fix.

#222 also addresses #199 (openshell path resolution in the bridge) which is part of the same propagation chain — the bridge fails on both missing SANDBOX_NAME and an unresolvable openshell binary when launched via nohup. Splitting them means a second PR touching the same files for a tightly coupled issue.

Happy to coordinate if maintainers prefer a different breakdown, but wanted to make sure the overlap is visible.

-BT

Thanks for flagging the overlap, @brianwtaylor. #222 covers the same root cause fix and also addresses #199, so it makes more sense to keep that as the single PR for this. Closing this one.