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

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

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

@@ -0,0 +1,44 @@
+"use strict";
+
+const { Op } = require("sequelize");
+
+const onlyDeleted = { deletedAt: { [Op.not]: null } };
+
+/**
+ * Soft-restore a single record by clearing deletedAt / deletedBy.
+ * Returns the record on success, null if not found.
+ *
+ * @param {Model}  Model       - Sequelize model
+ * @param {object} where       - Where clause (must include onlyDeleted or equivalent)
+ * @param {*}      restoredBy  - User ID stamped onto updatedBy
+ * @param {object} t           - Sequelize transaction
+ */
+async function restoreOne(Model, where, restoredBy, t) {
+  const record = await Model.findOne({ where, paranoid: false });
+  if (!record) return null;
+  
+  await record.restore(); 
+  await record.update({ updatedBy: restoredBy, deletedBy: null })
+
+  return record;
+}
+
+/**
+ * Soft-restore many records by their primary key column.
+ * Returns the count of restored 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 restore
+ * @param {*}      restoredBy  - User ID stamped onto updatedBy
+ * @param {object} t           - Sequelize transaction
+ */
+async function restoreMany(Model, pkColumn, ids, restoredBy, t) {
+  const [count] = await Model.update(
+    { deletedAt: null, deletedBy: null, updatedBy: restoredBy ?? null },
+    { where: { [pkColumn]: ids, ...onlyDeleted }, transaction: t, paranoid: false }
+  );
+  return count;
+}
+
+module.exports = { restoreOne, restoreMany };