feat(bisaya): update health gap exercise instruction for clarity

backend/migrations-active/20260907000001-clarify-bisaya-health-gap.cjs

@@ -0,0 +1,21 @@
+'use strict';
+
+/** The original body-part gap had several equally plausible answers. */
+module.exports = {
+  async up(queryInterface) {
+    await queryInterface.sequelize.query(`
+      UPDATE community.vocab_grammar_exercise AS exercise
+      SET instruction = 'Frage auf Bisaya: „Tut dir der Bauch weh? Geht es dir schon besser?“'
+      FROM community.vocab_course_lesson AS lesson
+      WHERE exercise.lesson_id = lesson.id
+        AND lesson.lesson_number = 26
+        AND lesson.title = 'Gesundheit & Wohlbefinden'
+        AND exercise.exercise_number = 2
+        AND exercise.title = 'Gesundheitsfrage ergänzen';
+    `);
+  },
+
+  async down() {
+    // The old wording did not identify the intended body part.
+  }
+};