fix(node-sdk): add async iterator support to EventStream for for-await-of loops

Fixes #10

- Add Symbol.asyncIterator method to EventStream prototype
- Update TypeScript type definitions
- Enables 'for await (const event of stream)' syntax
- EventStream.next() returns Promise<NextResult> with async iterator protocol

Author: RoyLin

sdk/node/index.d.ts

@@ -574,6 +574,8 @@ export declare class EventStream {
    * When `done` is true, the stream is exhausted.
    */
   next(): Promise<NextResult>
+  /** Async iterator protocol support for `for await...of` loops */
+  [Symbol.asyncIterator](): EventStream
 }
 /**
  * File-backed long-term memory store.

sdk/node/index.js

@@ -312,6 +312,11 @@ if (!nativeBinding) {
 
 const { EventStream, FileMemoryStore, FileSessionStore, MemorySessionStore, DefaultSecurityProvider, DocumentParserRegistry, StdioTransport, HttpTransport, WebSocketTransport, UnixSocketTransport, Agent, Session, builtinSkills, TeamTaskBoard, Team, TeamRunner, SubAgentHandle, Orchestrator } = nativeBinding
 
+// Add async iterator support to EventStream
+EventStream.prototype[Symbol.asyncIterator] = function() {
+  return this
+}
+
 module.exports.EventStream = EventStream
 module.exports.FileMemoryStore = FileMemoryStore
 module.exports.FileSessionStore = FileSessionStore