chore: replace gulp by a pure rollup based build

tools/convert-packs-to-json.js

@@ -0,0 +1,20 @@
+// SPDX-FileCopyrightText: 2021 Johannes Loher
+//
+// SPDX-License-Identifier: MIT
+
+import promises from "node:fs/promises";
+import path from "node:path";
+
+import { distDirectory, sourceDirectory } from "./const.js";
+import { convertPackFileToJSONFile } from "./json-pack-tools.js";
+
+const packsDistDirectory = path.join(distDirectory, "packs");
+const packsSourceDirectory = path.join(sourceDirectory, "packs");
+
+console.log(`Converting pack files in ${packsDistDirectory} to json files in ${packsSourceDirectory}:`);
+
+const conversionPromises = (await promises.readdir(packsDistDirectory, { withFileTypes: true }))
+    .filter((dirent) => dirent.isFile() && path.extname(dirent.name))
+    .map(async (dirent) => convertPackFileToJSONFile(path.join(packsDistDirectory, dirent.name), packsSourceDirectory));
+
+await Promise.all(conversionPromises);