Method observeInteractionEvent

packages/runtime/src/runtime-kernel.ts:2567–2614

* Track every request a session can park on until its settlement ack lands, * so a surface that was not mounted when the request streamed by can still * read it back and render the prompt (#2072).

(
    sessionId: string,
    backend: AgentBackend,
    event: SessionEvent,
  )

   * read it back and render the prompt (#2072).
   */
  private observeInteractionEvent(
    sessionId: string,
    backend: AgentBackend,
    event: SessionEvent,
  ): void {
    if (
      event.type !== 'sandbox_boundary_request' &&
      event.type !== 'user_question_request' &&
      event.type !== 'sandbox_boundary_decision_ack' &&
      event.type !== 'user_question_answer_ack'
    ) {
      return;
    }
    const key = interactionOwnerKey(sessionId, event.requestId);
    if (
      event.type === 'sandbox_boundary_decision_ack' ||
      event.type === 'user_question_answer_ack'
    ) {
      this.interactionRequestOwners.delete(key);
      return;
    }
    const generation = [...this.backendGenerations.values()].find(
      (candidate) =>
        candidate.sessionId === sessionId &&
        candidate.backend === backend &&
        candidate.phase !== 'terminated',
    );
    if (!generation) {
      throw new RuntimeInteractionInvariantError(
        `Interaction request ${event.requestId} has no active backend owner`,
      );
    }
    const existing = this.interactionRequestOwners.get(key);
    if (
      existing &&
      (existing.generation !== generation.generation || existing.turnId !== event.turnId)
    ) {
      throw new RuntimeInteractionInvariantError(
        `Interaction request ${event.requestId} has conflicting owners`,
      );
    }
    this.interactionRequestOwners.set(key, {
      sessionId,
      turnId: event.turnId,
      generation: generation.generation,
      request: event,
    });
  }

  private clearInteractionRequestOwners(sessionId: string, turnId: string): void {
    for (const [key, owner] of this.interactionRequestOwners) {