Extract CI scripts in separate files

.github/scripts/create-version-tag.cjs

@@ -0,0 +1,24 @@
+// Copyright 2025 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+
+// @ts-check
+
+/** @param {import('@actions/github-script').AsyncFunctionArguments} AsyncFunctionArguments */
+module.exports = async ({ github, context }) => {
+  const { owner, repo } = context.repo;
+  const version = process.env.VERSION;
+  const tagSha = process.env.TAG_SHA;
+
+  if (!version) throw new Error("VERSION is not defined");
+  if (!tagSha) throw new Error("TAG_SHA is not defined");
+
+  const tag = await github.rest.git.createRef({
+    owner,
+    repo,
+    ref: `refs/tags/v${version}`,
+    sha: tagSha,
+  });
+  console.log("Created tag ref:", tag.data.url);
+};