add timeline pkg to flutter

packages/z-timeline/scripts/copy-build.mjs

@@ -0,0 +1,20 @@
+import { cpSync, readFileSync, writeFileSync } from "node:fs";
+import { resolve, dirname } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const src = resolve(__dirname, "../build/web");
+const dest = resolve(__dirname, "../../../apps/web/public/flutter");
+
+cpSync(src, dest, { recursive: true });
+console.log(`Copied Flutter build: ${src} → ${dest}`);
+
+// Extract buildConfig from flutter_bootstrap.js so the React app can fetch it
+const bootstrap = readFileSync(resolve(dest, "flutter_bootstrap.js"), "utf-8");
+const match = bootstrap.match(/_flutter\.buildConfig\s*=\s*({.*?});/);
+if (match) {
+  writeFileSync(resolve(dest, "build_config.json"), match[1]);
+  console.log("Extracted build_config.json");
+} else {
+  console.warn("Could not extract buildConfig from flutter_bootstrap.js");
+}