XY-874 Surface loop status in operator readback

[yvette-carlisle]

Summary

• expose loop_status in status JSON/text, dashboard, queued attention, and post-review readback
• summarize review checkpoints, architecture recovery, and boundary checks in private evidence readback
• document operator-control-plane/runtime/evidence readback fields and add status/dashboard/evidence tests

Validation

• cargo make fmt
• cargo make lint-fix
• cargo make test (1035 passed, 1 skipped)
• git diff --check