fix: health score total with sum, instead of mean

Signed-off-by: Joana Maia <jmaia@contractor.linuxfoundation.org>

Author: joanagmaia

services/libs/tinybird/pipes/project_insights_copy.pipe

@@ -111,16 +111,26 @@ DESCRIPTION >
     - impactScoreRaw: MAX across the project's repos (each repo's own value is already a MAX over its
     published packages) — matches the spec's "MAX(packages.impact) over packages published by any
     repo in the project," since max-of-maxes = max-over-all.
+    - healthScoreV2: sum of the three per-category medians below, null-guarded per IN-1248 (NULL when
+    fewer than 2 categories are present). `quantileExactOrNull` is used instead of `quantileExact` so
+    the guard and coalesce can see NULL explicitly — `quantileExact` returns 0 on an empty set, which
+    would defeat the "< 2 categories → NULL" rule.
     - maintainerHealthScoreV2 / securitySupplyChainScoreV2 / developmentActivityScoreV2 (IN-1212):
-    independent per-category medians (`quantileExact(0.5)`) over repos where that category is non-NULL —
-    their repo set differs from healthScoreV2 (which includes repos with one imputed category), so they
-    do not necessarily reconcile with the project score. NULL when every repo is NULL for a category.
+    independent per-category medians (`quantileExact(0.5)`) over repos where that category is non-NULL.
+    NULL when every repo is NULL for a category.
 
 SQL >
     SELECT
         rep.insightsProjectId AS insightsProjectId,
-        quantileExact(0.5)
-        (hv2.healthScoreV2) AS healthScoreV2,
+        if(
+            (quantileExactOrNull(0.5)(hv2.maintainerHealthScoreV2) IS NOT NULL)
+            + (quantileExactOrNull(0.5)(hv2.securitySupplyChainScoreV2) IS NOT NULL)
+            + (quantileExactOrNull(0.5)(hv2.developmentActivityScoreV2) IS NOT NULL) < 2,
+            NULL,
+            coalesce(quantileExactOrNull(0.5)(hv2.maintainerHealthScoreV2), 0)
+            + coalesce(quantileExactOrNull(0.5)(hv2.securitySupplyChainScoreV2), 0)
+            + coalesce(quantileExactOrNull(0.5)(hv2.developmentActivityScoreV2), 0)
+        ) AS healthScoreV2,
         if(
             empty(groupArray(hv2.lifecycleLabelV2)),
             NULL,