[chat] adding plan/update plan blocks for threads

[visyat]

Adding basic post, edit, and task update operations for thread plans – unlocks the plan/task blocks in Slack for agent threads (status updates).

const plan = await thread.postPlan({
  initialMessage: "Starting...",
});
const result = await agent.generate({
  toolChoice: "required",
  prompt: message.text,
  onStepFinish: async (step) => {
    const { title: stepTitle, details: stepDetails } =
      getStepTaskTitleAndDetails(step);
    if (step.finishReason === "tool-calls") {
      // Single addTask: marks current complete and adds next in one edit (no flash).
      await plan.addTask({
        title: stepTitle,
        children: stepDetails.length > 0 ? stepDetails : undefined,
      });
    } else {
      await plan.updateTask({
        status: "complete",
        output: stepDetails.length > 0 ? stepDetails : undefined,
      });
    }
  },
  onFinish: async () => {
    await plan.complete({
      completeMessage: "AI finished",
    });
  },
});

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
chat	Ignored	Open in v0	Feb 25, 2026 11:29pm

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[cramforce]

Could you move this and related code into a new file?

[cramforce]

Before doing this: Are there other things like it?

We have avoided postX APIs so far.

Should we make a Plan. Then post it. And use regular edit. And eventually slack adapter can do its thing