build: reduce build log noise

scripts/tsdown-build.mjs

@@ -0,0 +1,19 @@
+#!/usr/bin/env node
+
+import { spawnSync } from "node:child_process";
+
+const logLevel = process.env.OPENCLAW_BUILD_VERBOSE ? "info" : "warn";
+const result = spawnSync(
+  "pnpm",
+  ["exec", "tsdown", "--config-loader", "unrun", "--logLevel", logLevel],
+  {
+    stdio: "inherit",
+    shell: process.platform === "win32",
+  },
+);
+
+if (typeof result.status === "number") {
+  process.exit(result.status);
+}
+
+process.exit(1);