chore: import upstream snapshot with attribution

integrations/filesystem-watcher/bin.mjs

@@ -0,0 +1,28 @@
+#!/usr/bin/env node
+import { FilesystemWatcher, configFromEnv } from "./watcher.mjs";
+
+const cliArgs = process.argv.slice(2);
+const envCfg = configFromEnv(process.env);
+
+const roots = cliArgs.length > 0 ? cliArgs : envCfg.roots;
+if (!roots || roots.length === 0) {
+  process.stderr.write(
+    "agentmemory-fs-watcher: no directories to watch.\n" +
+      "Usage: agentmemory-fs-watcher <dir> [<dir>...]\n" +
+      "Or set AGENTMEMORY_FS_WATCH_DIRS=path1,path2\n",
+  );
+  process.exit(2);
+}
+
+const watcher = new FilesystemWatcher({ ...envCfg, roots });
+watcher.start();
+process.stderr.write(
+  `[fs-watcher] emitting to ${envCfg.baseUrl || "http://localhost:3111"}\n`,
+);
+
+const shutdown = () => {
+  watcher.stop();
+  process.exit(0);
+};
+process.on("SIGINT", shutdown);
+process.on("SIGTERM", shutdown);