Fix measure count queries missing category column

CountByRiskID and CountByControlID CTEs did not include m.category in their SELECT
lists, causing "column category does not exist" errors when MeasureFilter applied
category constraints. Added m.category to both CTEs.

Also add comprehensive e2e tests for measure filtering by category at organization,
risk, and control levels.

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/coredata/measure.go

@@ -84,7 +84,8 @@ WITH msrs AS (
 		m.id,
 		m.tenant_id,
 		m.search_vector,
-		m.state
+		m.state,
+		m.category
 	FROM
 		measures m
 	INNER JOIN
@@ -195,7 +196,8 @@ WITH mtgtns AS (
 			m.id,
 			m.tenant_id,
 			m.search_vector,
-			m.state
+			m.state,
+			m.category
 		FROM
 			measures m
 		INNER JOIN