build: PaddedCell-style install.mjs + SDK-aligned packaging

install.mjs (--install/--build-only/--uninstall/--openclaw-profile-path),
tsconfig outDir dist/fabric, package.json openclaw file dep + main.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

node_modules/engine.io-client/build/esm/browser-entrypoint.js

@@ -0,0 +1,2 @@
+import { Socket } from "./socket.js";
+export default (uri, opts) => new Socket(uri, opts);