fix(vocab): exclude greeting tasks from SRS

backend/migrations-active/20261027000001-remove-srs-good-night-task-prompt.cjs

@@ -0,0 +1,16 @@
+'use strict';
+
+/** Removes a generated task instruction accidentally persisted as an SRS card. */
+module.exports = {
+  async up(queryInterface) {
+    await queryInterface.sequelize.query(`
+      DELETE FROM community.vocab_srs_item
+      WHERE course_id = 1
+        AND lower(trim(learning)) = 'wünsche einen guten abend, eine gute nacht und dass die person gut schlafen soll.';
+    `);
+  },
+
+  async down() {
+    // The invalid generated SRS cards must not be restored.
+  }
+};