Preferences: Add read-only APIServer for preferences and dashboard stars (#106109)

pkg/registry/apis/preferences/legacy/testdata/postgres--sql_preferences_query-user-no-teams.sql

@@ -0,0 +1,17 @@
+SELECT p.id, p.org_id,
+  p.json_data,
+  p.timezone,
+  p.theme,
+  p.week_start,
+  p.home_dashboard_uid,
+  u.uid as user_uid,
+  t.uid as team_uid,
+  p.created, p.updated
+ FROM "grafana"."preferences" as p 
+ LEFT JOIN "grafana"."user" as u ON p.user_id = u.id
+ LEFT JOIN "grafana"."team" as t ON p.team_id = t.id
+WHERE p.org_id = 1 
+  AND (u.uid = 'uuu'
+   OR p.user_id = 0
+  )
+ORDER BY p.user_id asc, p.team_id asc, p.org_id asc