added and fix some of things

Signed-off-by: Kenneth Obsequio <k80308392@gmail.com>

controllers/admin/lessons.controller.js

@@ -112,6 +112,29 @@ const LESSON_LIST_COMPUTED = [
       END
     )`,
   },
+  {
+    // Not its own column — consumed by the frontend's Subscription cell so a
+    // lesson gated only through an affiliated course (own `subscription` is
+    // NULL) still shows a tier instead of "-". Distinct tiers across every
+    // affiliated course, comma-joined (a lesson can reach several courses
+    // through several units, each possibly at a different tier).
+    key: "course_subscription",
+    label: "Course Subscription",
+    type: "text",
+    hidden: true,
+    filterable: false,
+    literal: `(
+      SELECT STRING_AGG(sub.subscription, ', ')
+      FROM (
+        SELECT DISTINCT c.subscription
+        FROM unit_lessons ul
+        JOIN units u ON u.unit_id = ul.unit_id AND u."deletedAt" IS NULL
+        JOIN course_units cu ON cu.unit_id = u.unit_id
+        JOIN courses c ON c.course_id = cu.course_id AND c."deletedAt" IS NULL
+        WHERE ul.lesson_id = "Lesson"."lesson_id"
+      ) sub
+    )`,
+  },
 ];
 
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