docs: add JSDoc headers to all externally exported store functions

src/store/article/deleteImage.js

@@ -1,6 +1,16 @@
 import { DELETE_BY_ARTICLE_AND_HASH } from '../../sql/pic.js';
 import resolveArticleBySku from './resolveArticleBySku.js';
 
+/**
+ * Deletes an image from an article by its SKU and full image hash.
+ *
+ * @param {object} pool - The mssql connection pool.
+ * @returns {Function} An async function that deletes an article image.
+ *
+ * @example
+ * const fn = deleteImage(pool);
+ * await fn(42, 'SKU-1', 'abc123');
+ */
 export default function deleteImage(pool) {
   const resolve = resolveArticleBySku(pool);