CI: test-online-updates-idle.py fails intermittently (checkpoint lines threshold) #255

The scripts (component 8.4|9.7) jobs in integration-scripts.yml fail on many unrelated PRs and pass on re-run. The failure is in scripts/test-online-updates-idle.py:

idle 10s: checkpoint lines | <= 1 | 5 | FAIL
Failed: test-online-updates-idle.py

The check expects at most 1 checkpoint log line during a 10 s idle window and sees about 5 on loaded CI runners.

Recent examples, all passing on re-run:

• fix(docker): base component images on their exact build release #245: run 41216934407
• fix(mcp-guard): guard sessions opened by components (RFC 0001 Phase 4, Q4) #252: runs 41334519311, 41339688723, 41344812524
• feat(docker): mysql-mcp images with component_mcp_guard and the tool pack (RFC 0001 Phase 3) #244: run 41200347851

The threshold looks timing-sensitive on shared runners. Options:

• widen it on CI;
• measure the idle window from the last write rather than from wall-clock;
• make it non-blocking in CI.

Filed from the RFC 0001 component work, which kept re-running it.