Fix Octo filesystem access and harden heartbeat delivery

[pmbstyle]

Summary

• keep Octo filesystem tools available even when the research profile is active
• harden heartbeat delivery so only explicit user-visible heartbeat results are sent outward
• add a strict heartbeat delivery rewrite pass so scheduled user-facing results are not lost when the model forgets the wrapper

Testing

• uv run pytest tests/test_heartbeat.py tests/test_cli_tools_resolve.py -q