Add WebSocket support and update dependencies

- Introduced WebSocket polyfill for Node.js in seed-activity.ts and seed-profiles.ts to support applesauce-relay and RxJS.
- Updated package.json and package-lock.json to include 'ws' version 8.19.0 and '@types/ws' version 8.18.1 as dependencies.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/seed-activity.ts

@@ -4,6 +4,12 @@
  *
  * Run after seed-profiles.ts and with the relay already running.
  */
+// Polyfill WebSocket for Node.js (required by applesauce-relay / RxJS)
+import WebSocket from 'ws'
+if (!globalThis.WebSocket) {
+  ;(globalThis as unknown as Record<string, unknown>).WebSocket = WebSocket
+}
+
 import { Relay } from 'applesauce-relay'
 import { PrivateKeySigner } from 'applesauce-signers/signers/private-key-signer'
 import {