galaxy(alarms): drop dead primitive branch from AlarmAttributesSql

B5: the candidate CTE's src_pri=1 (primitive-instance) UNION ALL branch was always
excluded by the final WHERE r.src_pri=0, so it added work with no output change. Remove
the branch and the now-constant src_pri column/filter. An alarm anchor is always a user
attribute, so output is identical.

src/ZB.MOM.WW.MxGateway.Server/Galaxy/GalaxyRepository.cs

@@ -308,11 +308,13 @@ LEFT JOIN data_type dt ON dt.mx_data_type = r.mx_data_type
 WHERE r.rn = 1
 ORDER BY r.tag_name, r.attribute_name";
 
-    // Alarm-only discovery for the subtag-fallback watch-list. This deliberately reuses the
+    // Alarm-only discovery for the subtag-fallback watch-list. This reuses the candidate/ranked
-    // exact candidate/ranked CTE structure and the same `AlarmExtension`-based is_alarm
+    // CTE shape and the same `AlarmExtension`-based detection as AttributesSql. Unlike
-    // detection as AttributesSql so the two queries cannot drift: a row qualifies only when
+    // AttributesSql it keeps only the user-attribute (dynamic_attribute) candidate branch: an
-    // its user attribute (src_pri 0) anchors an `AlarmExtension` primitive on the owning
+    // alarm anchor is always a user attribute, so the primitive-instance branch AttributesSql
-    // object. It projects just what the watch-list needs — full_tag_reference (tag_name +
+    // carries would be filtered out here anyway — a row qualifies only when its user attribute
+    // anchors an `AlarmExtension` primitive on the owning object. It projects just what the
+    // watch-list needs — full_tag_reference (tag_name +
     // '.' + attribute_name, matching AttributesSql) and the owning object's tag_name as
     // source_object_reference. The array `[]` suffix is intentionally omitted: an
     // alarm-bearing attribute is a scalar anchor, not an array body. It also projects the
@@ -332,7 +334,7 @@ ORDER BY r.tag_name, r.attribute_name";
 ),
 candidate AS (
     SELECT
-        dpc.gobject_id, g.tag_name, da.attribute_name, dpc.depth, 0 AS src_pri
+        dpc.gobject_id, g.tag_name, da.attribute_name, dpc.depth
     FROM deployed_package_chain dpc
     INNER JOIN dynamic_attribute da ON da.package_id = dpc.package_id
     INNER JOIN gobject g ON g.gobject_id = dpc.gobject_id
@@ -341,25 +343,10 @@ candidate AS (
         AND da.attribute_name NOT LIKE '[_]%'
         AND da.attribute_name NOT LIKE '%.Description'
         AND da.mx_attribute_category IN (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 24)
-    UNION ALL
-    SELECT
-        dpc.gobject_id, g.tag_name,
-        CASE WHEN pi.primitive_name IS NULL OR pi.primitive_name = ''
-             THEN ad.attribute_name
-             ELSE pi.primitive_name + '.' + ad.attribute_name END AS attribute_name,
-        dpc.depth, 1 AS src_pri
-    FROM deployed_package_chain dpc
-    INNER JOIN primitive_instance pi ON pi.package_id = dpc.package_id
-    INNER JOIN attribute_definition ad ON ad.primitive_definition_id = pi.primitive_definition_id
-    INNER JOIN gobject g ON g.gobject_id = dpc.gobject_id
-    INNER JOIN template_definition td ON td.template_definition_id = g.template_definition_id
-    WHERE td.category_id IN (1, 3, 4, 10, 11, 13, 17, 24, 26)
-        AND ad.attribute_name NOT LIKE '[_]%'
-        AND ad.attribute_name NOT LIKE '%.Description'
 ),
 ranked AS (
     SELECT c.*, ROW_NUMBER() OVER (
-        PARTITION BY c.gobject_id, c.attribute_name ORDER BY c.src_pri, c.depth) AS rn
+        PARTITION BY c.gobject_id, c.attribute_name ORDER BY c.depth) AS rn
     FROM candidate c
 )
 SELECT
@@ -370,7 +357,6 @@ FROM ranked r
 INNER JOIN gobject g ON g.gobject_id = r.gobject_id
 LEFT JOIN gobject area ON area.gobject_id = g.area_gobject_id
 WHERE r.rn = 1
-    AND r.src_pri = 0
     AND EXISTS (
         SELECT 1 FROM deployed_package_chain dpc2
         INNER JOIN primitive_instance pi ON pi.package_id = dpc2.package_id AND pi.primitive_name = r.attribute_name