feat: add multi-engine regex flavour support

scripts/build-go-engine.mjs

@@ -0,0 +1,15 @@
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import { buildGoPack } from "./go-engine-pack.mjs";
+
+const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
+const arguments_ = process.argv.slice(2);
+if (arguments_.length < 1 || arguments_.length > 2) {
+  throw new Error(
+    "Usage: node scripts/build-go-engine.mjs GO_ROOT [.engine-build/go]",
+  );
+}
+const result = await buildGoPack(root, arguments_[0], arguments_[1]);
+console.log(
+  `Built and verified ${result.metadata.semanticIdentity} at ${result.output}.`,
+);