chore: relocate backend into apps/api ahead of monorepo merge

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

apps/api/utils/courses/permanentDelete.util.js

@@ -0,0 +1,45 @@
+"use strict";
+
+const { Op } = require("sequelize");
+
+const onlyDeleted = { deletedAt: { [Op.not]: null } };
+
+/**
+ * Permanently delete a single archived record.
+ * Returns the record on success, null if not found, false if found but not archived.
+ *
+ * @param {Model}  Model - Sequelize model
+ * @param {object} where - Where clause (primary key lookup)
+ * @param {object} t     - Sequelize transaction
+ */
+async function permanentDeleteOne(Model, where, t) {
+  const record = await Model.findOne({ where, paranoid: false, transaction: t });
+  if (!record) return null;
+  if (!record.deletedAt) return false;
+
+  await record.destroy({ force: true, transaction: t });
+  return record;
+}
+
+/**
+ * Permanently delete many archived records by primary key.
+ * Returns the count of deleted records.
+ *
+ * @param {Model}  Model    - Sequelize model
+ * @param {string} pkColumn - Primary key column name (e.g. "course_id")
+ * @param {Array}  ids      - Array of primary key values to delete
+ * @param {object} t        - Sequelize transaction
+ */
+async function permanentDeleteMany(Model, pkColumn, ids, t) {
+  if (!ids?.length) return 0;
+
+  const count = await Model.destroy({
+    where: { [pkColumn]: ids, ...onlyDeleted },
+    transaction: t,
+    paranoid: false,
+    force: true,
+  });
+  return count;
+}
+
+module.exports = { permanentDeleteOne, permanentDeleteMany };