Collapse overlapping probe versions conservatively

A hosted probe edit can leave old and new configuration series inside the same alert lookback. Joining the raw series may fail with duplicate matches, while simply taking a maximum can turn disagreement into false certainty. Reduce to the finite identity labels only when overlapping versions agree on slot and outcome; treat disagreement or unknown outcomes as unknown availability. This creates a short blind window after some edits, so a separate coverage view remains useful. Test both agreeing and conflicting versions with the real query engine.

Applies when: A monitoring platform emits overlapping metric series during probe configuration changes. Keywords: synthetic probe config version duplicate series PromQL join consensus unknown downtime