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-debug/browser-entrypoint.d.ts

@@ -0,0 +1,3 @@
+import { Socket } from "./socket.js";
+declare const _default: (uri: any, opts: any) => Socket;
+export default _default;