feat: expose worker lifecycle activity

[dataforxyz]

Summary

• emit content-free inbound sender metadata after durable Intercom acceptance
• relay orchestrator-generated lifecycle checkpoint messages without an LLM tool call
• preserve duplicate/reply semantics while giving the manager a reliable activity signal
• compose cleanly with structured controls: registered control traffic is consumed separately and does not renew worker lifecycle activity

Why

Persistent fleet leases were renewed from manager heartbeat/process existence, allowing silent workers to remain alive indefinitely. The orchestrator now renews only from exact worker-originated messages or explicit manager renewal. This adapter event bridge provides the Pi-manager activity source and checkpoint delivery path.

Security

• event payload excludes message bodies and attachments
• orchestrator matches the broker-stamped stable sender ID, not display name
• registered structured controls do not count as worker activity
• no credential or remote-access fields are added

Verification

• npm run typecheck
• npm test — 161/161 after rebasing on structured-control transport
• integration coverage proves inbound activity metadata contains no message body, registered control messages do not renew lifecycle activity, and lifecycle relay wakes the target

Coordinated with:

• feat: expire idle workers safely orcboss#4
• feat: renew workers from manager activity agent-intercom-opencode#2

[dataforxyz]

Independent lifecycle review result before rebase: APPROVE — no blockers.

After rebasing onto the structured-control transport, registered control messages are consumed before lifecycle activity emission so control-plane traffic cannot keep a worker alive. A focused integration test covers that boundary; full local verification is 161/161.