fix: off-by-one in runContainer16.getCardinalityInRange for intra-container gaps

When the query range falls entirely in a gap between two run intervals
within the same container, the early-return guard "lastIdx < firstIdx-1"
misses the case where lastIdx == firstIdx-1, causing the next interval
(outside the query range) to be counted.

Fix: change the condition to "lastIdx < firstIdx".

Author: ValentaTomas

runcontainer.go

@@ -2543,7 +2543,7 @@ func (rc *runContainer16) getCardinalityInRange(start, end uint) int {
 	if firstIdx >= len(rc.iv) {
 		return 0
 	}
-	if lastIdx < 0 || lastIdx < firstIdx-1 {
+	if lastIdx < 0 || lastIdx < firstIdx {
 		return 0
 	}