feat(quiz): variety in quiz question selection

Expand the seeded pool from 12 to 36 questions (migration 0020) and
select 10 per session preferring questions the couple has never seen,
then least recently used, with random tiebreaks, so repeat quizzes stop
serving the same set.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/api/drizzle/meta/_journal.json

@@ -141,6 +141,13 @@
       "when": 1788168000000,
       "tag": "0019_quiz",
       "breakpoints": true
+    },
+    {
+      "idx": 20,
+      "version": "7",
+      "when": 1788168060000,
+      "tag": "0020_quiz_question_pool",
+      "breakpoints": true
     }
   ]
 }