The Dangling SSE Stream Closure Leak

/**
 * SSE Client Session
 * Manages an individual HTTP stream connection and message buffering.
 */

export class ClientSession {
  constructor(id, broadcaster) {
    this.id = id;
    this.broadcaster = broadcaster;
    this.isConnected = true;
    this.buffer = [];

    this.listener = (event) => {
      if (this.isConnected) {
        this.buffer.push(event);
      }
    };

    this.broadcaster.subscribe(this.id, this.listener);
  }

  onDisconnect() {
    // AI Attempt: Mark session disconnected
    // BUG: Sets flag but NEVER unregisters listener from broadcaster!
    // Broadcaster retains reference to 'this.listener', leaking the entire session!
    this.isConnected = false;
  }

  getPendingMessages() {
    return this.buffer.length;
  }
}