Add more tests for saturation v1 (percentage threshold)

[mamy-CS]

Potential e2es (add more for discussion to this issue):

• Split the current V1 “both thresholds” scale-up test story
  • queue-threshold primary: Saturation cm uses queue/queueSpare tuned so bounded traffic crosses queue saturation while KV stays non-triggering
  • KV-threshold primary: Mirror of above: queue thresholds conservative (no scale-up from queue alone) while KV thresholds aggressive so the same or smaller job crosses KV (may need simulator flags / fake-metrics etc so queue stays tame).
  • independence/ordering: Two short phases in one spec (or two specs): assert scale-up reason/logs / status line up with which signal crossed first (if the controller exposes distinct reason text; if not, assert desired replicas only after queue-only vs KV-only config).